Vehicle seat with inflatable bladder

ABSTRACT

A vehicle seat having a bladder with more than two inflatable chambers and an integral control flap, all of one piece, integral construction. To maximize inflatable volume of each chamber, each chamber preferably has a sidewall portion that is generally perpendicular. The control flap has passages in communication with the chambers and valving for selectively controlling inflation of the chambers. Valving preferably includes pinch valves having a generally T-shaped body with legs that pinch passages in the control flap to retain gas in a chamber and selectively inflate or deflate the chamber. The bladder is connected to a gas supply having a pump in communication with a reservoir for storing a charge of pressurized gas in the reservoir so that the pump need not immediately operate when gas is needed to inflate a chamber. To maintain a charge of gas in the reservoir, the gas supply preferably includes a pressure switch for energizing the pump when the reservoir pressure drops below a lower threshold and deenergizing the pump when pressure rises above an upper threshold. A preferred bladder has a chamber for cushioning the thighs of a seat occupant, a chamber for cushioning the buttocks and can have a chamber for providing lumbar support. A bladder of this invention can be assembled as part of a motorcycle seat having a bladder for the driver and a bladder for the passenger. The bladder also can be used in automotive and off road vehicle seating applications.

FIELD OF THE INVENTION

This invention relates generally to vehicle seating which utilizesinflatable bladders to improve comfort while preventing fatigue and moreparticularly to a vehicle seat having an inflatable bladder of onepiece, unitary construction with multiple chambers in communication withan integral control flap for enabling easy construction of the bladderand simple assembly of the bladder to a seat.

BACKGROUND OF THE INVENTION

Often people spend a great deal of time seated each day, whether it bein an office chair, in a car, in a truck, or riding a motorcycle. Often,the seats have virtually no way of being adjusted so that they can bemade more comfortable to a person sitting in the seat. As a result,seats with little or no adjustability can be very uncomfortable to sitin, particularly for long periods of time. Additionally, such seatingcan contribute to fatigue or can improperly support body parts of theperson sitting in the seat, such as, for example, resulting in poorlumbar support to the lower back of the seat occupant, which canundesirably increase fatigue by making the body part sore or stiff.Moreover, lack of adjustability can result in a seat occupant beingpoorly positioned relative to another object, such as the steering wheelof an automobile or the handlebars of a motorcycle. Finally, sincepeople come in many different shapes, sizes, and weights, a seat lackingadequate adjustability may not properly fit a particular type or size ofperson, also making it very uncomfortable for that person to remainseated for long periods of time without experiencing discomfort orfatigue.

In light of all of these difficulties, seating designers have attemptedto design seats which are adjustable in many different ways to improvecomfort, decrease fatigue, properly position the seat occupant, andcomfortably fit people of a wide variety of sizes, shapes and weights.However, seat design can be very complicated, particularly for vehicleseating designers. For example, it is known by vehicle seat designersthat comfort to a seat occupant can be extremely important to the safetyof the seat occupant. Therefore, vehicle seat designers attempt todesign seats such that occupants having different body dimensions do notsuffer driving fatigue, which can be detrimental to safety.

There are other factors that a seat designer must contend with as well.For example, it is desirable that a vehicle seat provide proper supportto individual body areas by controlling how the pressure of the seatagainst a seat occupant is distributed. Additionally, it is preferredthat a seat provide adequate lateral support to a seat occupant when thevehicle is turning while enabling the occupant to relatively freelyadjust their sitting position without needing to readjust the seat.

Moreover, the components responsible for enabling seat adjustment mustnot adversely affect the vibrational and damping characteristics of theseat by preventing the natural frequency of the seat from falling withina range of excitation frequencies that are likely to be encounteredduring operation. Therefore, the distribution of the spring rates in theareas of the seat cushion and backrest where the adjustable componentsare located, as well as the overall spring rate and dampening capacityof the seat, must not be adversely affected by the use and operation ofthe adjustable components. Finally, all of the components which enableseat adjustability must be conveniently packaged within the seat whilealso not undesirably affecting the appearance of the seat.

To enhance seat occupant comfort, overlays or cushions have beendeveloped that have one or more inflatable chambers. One such seatoverlay, in the form of a seat cushion, is disclosed in Wilson, U.S.Pat. No. 3,540,776. These overlays are typically placed over a seat andinflated before the seat occupant sits down to enhance the comfort ofthe seat occupant. Unfortunately, these overlays are not specificallydesigned to maximize comfort for a specific seat contour but rather aredesigned to be used with any type of seat. As a result, these overlayscan be more effective at preventing discomfort and fatigue when usedwith some types of seats and not with other types of seats.

Moreover, these overlay cushions are not particularly well suited foruse in automotive vehicles because they can slip and slide around makingthem difficult to properly position for maximum comfort and because theycan be easily damaged during use. Additionally, these overlays typicallymust be manually inflated and will leak over time, undesirably requiringperiodic and time consuming manual reinflation.

Finally, the amount of cushioning provided by such an overlay is alsolimited because each chamber typically has a generally rounded "pillow"shaped construction which limits the inflated volume of the chamberthereby also limiting how deeply each chamber can be compressed duringcushioning a seat occupant during use and operation of the overlay. Toachieve greater cushioning, the surface area of a "pillow" shapedinflatable chamber can be increased to enable it to expand outwardly agreater distance when fully inflated. Unfortunately, such a larger,"pillow" shaped inflatable chamber requires a greater volume of air toinflate, which can be time consuming. Additionally, a "pillow" shapedchamber may not always uniformly apply pressure to the desired body partof the seat occupant thereby possibly reducing the amount of comfortthat can be achieved.

The use of an air bladder having such a "pillow" inflatable chamberconstruction is less desirable for use with motorcycle seats becausetheir seats are smaller, reducing the amount of cushioning that a"pillow" shaped inflatable chamber can provide because of the limitedsurface area available on the motorcycle seat limiting its maximuminflatable volume. Finally, it is virtually impossible to produce aninflatable overlay or bladder with individual inflatable chambers havingthe "pillow" construction because of the limited surface area reducingthe surface area available for each chamber limiting the maximumcushioning available for a multi-chamber motorcycle seat overlay orbuilt in inflatable bladder.

In other instances, inflatable bladders that are built into the seathave been used to provide adjustment to increase comfort and reducefatigue. Examples of such built-in bladders are found in Flajole, U.S.Pat. No. 2,938,570, Isono et al., U.S. Pat. No. 4,592,588, and Ishida,et al., U.S. Pat. No. 4,807,931. These types of bladders cannot beeasily manually inflated and typically require some source of air, suchas from a hand bulb pump or another type of pressurized air supply, toinflate the bladder. For bladders which have more than one inflatablechamber, rather elaborate and complicated valving and air distributionarrangements have been developed, the assembly and installation of whichare not cost effective particularly in light of the competitive economicclimate that exists today in the automotive and off-road vehicleindustries.

For example, Isono, et al., U.S. Pat. No. 4,592,588 discloses a vehicleseat having separate independently inflatable bladders received incompartments within the seat and underneath the seat cover.Unfortunately, each bladder is of separate and independent constructionfrom every other bladder and requires separate insertion of each bladderinto its compartment during assembly undesirably increasing the numberof assembly steps as well as the cost to assemble a vehicle seat of thedisclosed construction. Moreover, as a result of each bladder beingindependent of every other bladder, conduit or piping must be attachedto each bladder and manually routed to an air supply which can evenfurther undesirably increase assembly costs.

SUMMARY OF THE INVENTION

A vehicle seat having an inflatable bladder of one piece, unitaryconstruction and possessing multiple inflatable chambers for enabling aseat occupant to separately and selectively inflate different chambersof the bladder to tune the firmness of various portions of the seat tothe individual preference of the seat occupant for providing cushioningand comfort while also preferably preventing fatigue. To facilitateconstruction of the bladder and its assembly to a seat, the bladder alsopreferably has an integral control flap with valving that enables thechambers of the bladder to be selectively inflated and deflated.

To provide gas on demand to inflate one or more chambers of the bladder,the inflatable bladder receives gas from a gas supply that is comprisedof a gas pump received in a gas reservoir. To enable gas to be virtuallyinstantaneously supplied to the bladder without immediately requiringthe pump to operate, the reservoir is charged by the pump with gashaving a pressure that preferably is greater than the pressure of gaswithin the bladder. To ensure that gas is available upon demand, thesupply preferably also includes a pressure switch in communication withthe pump for sensing pressure in the reservoir and energizing the pumpwhen the pressure in the reservoir drops too low.

The bladder of this invention is preferably constructed of a blank of aflexible and resilient material, such as preferably a urethane, that canbe formed and molded having a gas tight seal that defines gas passagesand inflatable chambers of the bladder along with an integral controlflap. A preferred embodiment of a bladder of this invention has twopairs of inflatable chambers, with the chambers constructed and arrangedsuch that a first pair of chambers preferably provides adjustablecushioning support to the femur and ischium skeletal structure of a seatoccupant and a second pair of chambers preferably provides adjustablecushioning support to the tuberosity of ischium and ramus of ischiumskeletal structure of the seat occupant. The first pair of inflatablechambers preferably also supports the biceps and gluteus maximus of themuscle structure of the seat occupant and the second pair of inflatablechambers preferably also supports the gluteus maximus.

In addition to the aforementioned bladder chambers, another preferredembodiment of a bladder of this invention has a third pair of chambersfor providing adjustable cushioning support to the lumbar region of theseat occupant by supporting the posterior crest of ilium and sacralvertebra of the skeletal structure. The third pair of inflatablechambers also provides support to the erector spinae and gluteus maximusmuscles of the muscle structure of the seat occupant.

During use of the bladder, as the first bladder chambers are inflated,it increases pressure on the femur and biceps of the seat occupant andthereby easing pressure on the ischium and gluteus maximus of the seatoccupant. As the second set of chambers is inflated, pressure isincreased on the tuberosity of ischium and gluteus maximus and pressureon the ramus of ischium is reduced. As the third set of chambers isinflated, pressure on the erector spinae and posterior crest of ilium isincreased, while pressure on the gluteus maximus and sacral vertebra isreduced.

To enable gas to flow to and from the bladder chambers, the control flaphas gas passages in communication with each pair of chambers to enablegas to be admitted into the chambers to inflate them and to allow gas tobe exhausted from the chambers to deflate them. To enable each pair ofchambers to communicate gas between each other, the bladder alsopreferably has a gas passage between each pair of chambers. If it isdesired to control the shape of a chamber during inflation, as well asits shape and behavior under load, an inflatable chamber can have one ormore relief indentions or recesses.

To enable gas to be selectively introduced by a seat occupant into aspecific chamber or chambers of the bladder, the control flap preferablyhas accommodations for valving. In a preferred control flap embodiment,the control flap has an inlet port that communicates gas from the supplyto a manifold which, in turn, has supply passages leading to each pairof inflatable chambers. The control flap preferably also has outletpassages in communication with the supply passages for enabling gas tobe exhausted from the inflatable chambers. Preferably, gas exhaustedfrom a chamber is relieved through exhaust ports in the outlet passages.

In a preferred control flap embodiment, the control flap and bladder areconstructed of a pair of urethane sheets secured together by one or moreseals defining inflatable chambers and gas passages within the bladderand control flap. The control flap has openings in its gas passagewaysleading to each inflatable chamber exposed by pulling apart the sheets.With the sheets urged apart, the nipples of a pneumatic valve assemblycan be inserted into the openings of each gas passageway of the controlflap. When the sheets are released, the sheets contract around thenipples to form a gas tight control flap and valve assembly.

Preferably, the gas used to inflate the bladder is air. If desired, thegas can be carbon dioxide, nitrogen, helium, or another gas that ispreferably compressible. If desired, a fluid can also be used to inflateone or more chambers of the bladder.

In a preferred bladder embodiment, pinch valves are used to enable aseat occupant to selectively inflate or deflate chambers of the bladder.Each pinch valve is comprised of a generally T-shaped valve body havinga valve stem that extends through an opening in the control flapadjacent the supply and outlet passages of an inflatable chamber. Thevalve body also has outwardly extending legs which are preferablyoriented such that they can be made to bear against one or both passagesfor retaining gas in the chamber, admitting gas into the chamber tocontrollably inflate it, or exhausting gas from the chamber to deflateit. The valve body is preferably urged toward its gas retaining positionby a spring located between the control flap and a cap fixtured to thefree end of the valve stem.

To facilitate pivoting of the valve body between a gas admittingposition, to inflate the chamber, and a gas exhausting position, todeflate the chamber, there preferably is a cover panel or bezel that ispreferably located between the control flap and biasing spring. Tofacilitate assembly, the cover panel can be sewn to a sidewall portionof a covering of the seat, thereby also helping to locate and anchor thecontrol flap.

Preferably, each leg of the valve body has an upraised boss that bearsagainst a gas passage of the control flap when biased by the springagainst the passage causing the passage to be pinched closed.Preferably, the construction and arrangement of the spring, cover panel,and valve body enables each leg to be biased against a gas passage ofthe control flap with enough force to pinch off and gas tightly seal thepassage thereby preventing gas flow through the passage.

To further facilitate operation of the valve, the cover panel preferablyhas valve seats adjacent each gas passage of the control flap to helpseat the boss of each valve leg against the passage, at least when thevalve is in its gas retaining position. Preferably, each valve seat is arecess, indention, or hole in the cover panel which overlies a gaspassage of the control flap and which is substantially complementarywith the shape of that portion of the valve leg which pinches closed thepassage, at least when the valve is in the gas retaining position.

In operation of a pinch valve, the valve can be moved between a gasadmitting position, enabling inflation of a chamber, a gas exhaustingposition, enabling deflation of the chamber, and a gas retainingposition, for retaining gas already received in the chamber. To inflatea chamber, the valve is preferably manually urged by the seat occupanttoward its gas admitting position where the valve body pivots such thatone of its legs maintains pinching pressure against the outlet passageof the control flap while the other leg moves away from the supplypassage, thereby opening the supply passage and allowing gas from thegas supply to flow through the passage into the chamber. To deflate thechamber, the valve is preferably manually urged toward its gasexhausting position where the valve body is pivoted such that one of itslegs maintains pinching pressure against the supply passage while itsother leg moves away from the outlet passage, thereby permitting gas toflow from the chamber through the outlet passage and out its exhaustport. When released by the seat occupant, the spring preferably returnsthe valve body to the gas retaining position with one of its legspinching closed the supply passage and the other of its legs pinchingclosed the outlet passage.

The gas supply has a reservoir that preferably is a bag that ispreferably gas tightly sealed for storing a charge of gas inside the bagfor enabling one or more chambers of the bladder to be inflated ondemand by the seat occupant. To enable the bag to be charged with gas,the pump is received inside the bag and has an inlet in communicationwith a gas source, such as preferably the outside atmosphere, and anoutlet in communication with a supply line that is connected to theinlet port of the control flap. Preferably, the pump is a compressorable to fill the reservoir bag with enough gas such that the pressure ofgas within the bag is greater than the pressure of gas within thebladder, at least while the valving of the bladder is in the gasretaining position.

To enable the compressor to charge and recharge the reservoir bag with asufficient amount of pressurized gas, the pressure switch is connectedto the compressor and senses the gas pressure within the bag. Thepressure switch preferably energizes the compressor when pressure withinthe bag has dropped below a desired threshold pressure, P₁, to cause thecompressor to recharge the bag with gas. The pressure switch preferablyshuts off the compressor when pressure within the bag has risen to atleast a desired upper threshold pressure, P₂.

Therefore, the pressure switch causes the compressor to recharge thereservoir bag with gas when the pressure in the bag drops below thelower threshold pressure, P₁, and energizes the compressor until thepressure within the bag reaches the upper threshold pressure, P₂. Forexample, the operating characteristics of the pressure switch preferablycan be chosen such that P₁ is about 13 pounds per square inch (psi) andP₂ is about 18 psi to sufficiently charge the bag with gas such that thecompressor need not immediately have to energize upon a valve of thebladder being moved to its gas admitting position until the pressurewithin the bag drops below 13 psi. Alternatively, a vacuum switchreceived inside the reservoir bag could also be used to controloperation of the gas compressor in the same manner.

A preferred bag embodiment is constructed of two sheets of urethane witha seal about its periphery defining its sidewalls and joining the sheetstogether. One end of the bag has breaks in the seal for an inlet toprovide an opening for an inlet to the gas compressor, an opening forthe gas supply line leading to the bladder, a gas tight conduit forelectrical wiring for both the compressor and switch, and a referenceport conduit, if necessary, for the reference port of a vacuum orpressure switch. If a vacuum switch is used to control compressoroperation, it is preferably received in the reservoir bag and has areference port in communication with the atmosphere outside the bag forproviding a reference pressure to the switch. To control compressoroperation, the switch is wired to a power source in series with thecompressor.

In constructing the bladder, a formable and moldable blank is preferablypreheated, formed, and molded. Preferably, the blank is constructed of apair of sheets that are preheated before being formed by vacuum forming.During vacuum forming and while each sheet preferably is still hot, avacuum mold imparts to each sheet a desired three dimensional contoursuch that chambers, gas passages, and a control flap are formed. Aftervacuum forming, the two sheets are joined or bonded together forming agas tight seal, further defining the chambers and gas passages of thebladder and gas passages of the control flap. Preferably, the sheets areformed such that at least a portion of the sidewall of each inflatablechamber of the bladder is generally perpendicular to the plane of theseal or an exterior wall of the chamber for maximizing the inflatablevolume of the chamber relative to the surface area of its top wall.

After molding and once sufficiently cool, the bladder is assembled to avehicle seat by placing it into retainer pockets in a foam supportcushion of the seat before further assembling a seat covering over thebladder and foam cushion.

Objects, features and advantages of this invention are to provide a seathaving an inflatable bladder which enables seat comfort to be easily andselectively adjusted by a seat occupant until a desired level orcombination of firmness and comfort is achieved; provides separately andvariably adjustable inflatable cushioning support to desired portions ofthe body of a seat occupant for enabling comfort to be tailored to seatoccupants of different shapes, sizes and weights; can be used with seatsof irregular shape and relatively small size; is well suited for use ina motorcycle seat; is versatile in that it can be used in automotive andoff road vehicle seating; can be constructed from a single blank ofmaterial, yet results in a bladder of one piece, unitary constructionhaving multiple inflatable chambers facilitating quick and easy seatassembly thereby minimizing assembly steps required to construct theseat; has inflatable chambers with generally perpendicular sidewalls formaximizing the inflatable volume of each chamber relative to the surfacearea of the chamber; is constructed with generally perpendicular chambersidewalls for maximizing the downward displacement that each inflatablechamber is capable of undergoing when absorbing a load on the bladder;can be made using a vacuum forming and molding process that isrelatively simple and economical and which produces a seal of goodintegrity defining chambers and gas passages in the bladder; has acontrol flap that is integral with the bladder for economicalmanufacture and simple seat assembly; utilizes a gas supply that caninstantaneously provide gas to the bladder without having to wait forits pump or compressor to supply gas; utilizes a method of providing asupply of gas for inflating the bladder that makes available gas toinflate the bladder without having to wait for the pump or compressor tobegin operation to supply the gas; utilizes a pinch valve of simple andeconomical construction for use in regulating gas flow into and out ofeach bladder chamber; is a bladder of rugged and durable construction,is easy to manufacture and assemble, is of simple design, economicalmanufacture, and is easy to use.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, features, and advantages of this invention willbecome apparent from the following detailed description of the bestmode, appended claims, and accompanying drawings in which:

FIG. 1 is a perspective view of a vehicle seat with its seat covercutaway to expose an inflatable bladder of this invention;

FIG. 2 is a perspective view of the bladder and a gas supply having areservoir and pump for providing gas to inflate the bladder and apressure switch for controlling operation of the pump;

FIG. 3 is a top view of the bladder of FIG. 2 showing more clearly itscontrol flap for controlling air flow into and out of inflatablechambers of the bladder and depicting schematically the construction andarrangement of the air supply and pressure switch;

FIG. 4 is a cross sectional view of the bladder taken along line 4--4 ofFIG. 3 shown with the covering of the seat broken away for clarity andthe bladder carried by a foam support cushion of the seat;

FIG. 5 is an enlarged fragmentary view of a preferred embodiment of thecontrol flap showing in more detail the construction and arrangement ofpinch valves for controlling air flow into and out of inflatablechambers of the bladder;

FIG. 6 is an enlarged fragmentary cross sectional view of the controlflap showing the pinch valve in its gas retaining position pinchingclosed both a supply passage and an outlet passage of the control flap;

FIG. 7A is an enlarged fragmentary cross sectional view of the controlflap showing the pinch valve in a gas admitting position pinching theclosed the outlet passage while allowing gas flow through the supplypassage to inflate a chamber of the bladder;

FIG. 7B is an enlarged fragmentary cross sectional view of the controlflap showing the pinch valve in a gas exhausting position pinchingclosed the supply passage while allowing gas flow through the outletpassage to deflate a chamber of the bladder;

FIG. 8 is an enlarged fragmentary cross sectional view of anotherpreferred embodiment of the control flap showing connection nipples ofthe flap for attachment to connection nipples of pneumatic valving forenabling the bladder to be selectively and controllably inflated anddeflated;

FIG. 9 is a front view of the pneumatic valving;

FIG. 10 is an enlarged fragmentary perspective view of another preferredembodiment of a control flap and valving assembly;

FIG. 11 is a side view of the control flap and valving assemblyembodiment shown in FIG. 10 after assembly has been completed;

FIG. 12 illustrates a forming and molding apparatus having a pair ofvacuum molds for constructing the bladder;

FIG. 13 shows a top view of a vacuum forming mold used to construct thebladder;

FIG. 14 illustrates the mold halves clamped together forming and moldingthe bladder;

FIG. 15 is an exploded perspective view of a motorcycle seat having aseat saddle, a single bladder for the driver of the motorcycle, and aseat covering which overlies the saddle and bladder;

FIG. 16A is an enlarged fragmentary perspective view of the gas supplyshowing in more detail a reservoir having a compressor (in phantom)received in the reservoir and a pressure switch in communication withthe reservoir for sensing the pressure of air within the reservoir forcontrolling operation of the compressor;

FIG. 16B is an enlarged top view of a preferred gas supply embodimenthaving a vacuum switch received inside the reservoir of the gas supply;

FIG. 17 is a bottom perspective view of the vehicle seat showing aretainer pocket in the seat saddle for receiving the air supply;

FIG. 18 is a perspective view of another motorcycle seat having abladder for the driver, a bladder for a passenger, and pneumatic valvingfor controlling operation of each bladder;

FIG. 19 is an exploded perspective view of the motorcycle seat depictingin more detail the first and second bladders, their air supply, andpneumatic valving;

FIG. 20 is a perspective view of a vehicle seat depicting in phantom apreferred embodiment of the bladder of this invention assembled into abackrest of the seat and another preferred embodiment of the bladder ofthis invention assembled into a cushion of the seat; and

FIG. 21 depicts an exploded view of the vehicle seat of FIG. 20 showingthe bladders in more detail.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates an inflatable bladder 40 of this invention for avehicle seat 42, such as a motorcycle seat 44, that has chambers 46which can be selectively and variably inflated by a seat occupant toachieve a desired level of comfort while riding in or operating avehicle, such as a motorcycle, M. As is shown in FIG. 1, the vehicleseat 42 has a seat cushion 48 that carries the bladder 40 and a sidewallportion 50 that receives and preferably carries an integral control flap52 of the bladder 40 that is conveniently positioned for enabling thechambers 46 of the bladder 40 to be selectively inflated by a seatoccupant during operation. Preferably, the bladder 40 has gas passages54 leading from the control flap 52 to the chambers 46 for enabling agas, such as preferably air, to be admitted into one or more of thechambers 46 to inflate them and also for enabling gas to be exhaustedfrom one or more of the chambers 46 to deflate them. To enable gas to becontrollably admitted and exhausted from the bladder 40 to control theamount of inflation of each chamber or set of chambers, the control flap52 has one or more valves 56. To facilitate assembly to a vehicle seat,the chambers 46, control flap 52, and gas passages 54 makeup a bladder40 of preferably one-piece, unitary construction for facilitating quickand simple assembly to a seat.

I. INFLATABLE BLADDER SYSTEM

FIGS. 2-4 further illustrate a preferred embodiment of the inflatablebladder 40 of this invention. Preferably, the bladder 40 is coupled by asupply line 58 to a gas supply 60 for providing gas under pressure toone or more inflatable chambers 46 of the bladder 40 to inflate thedesired chamber or chambers 46. To ensure that the gas supply 60 has asufficient amount of gas to adequately supply gas to the bladder 40during use and operation, the gas supply 60 preferably communicates witha pressure sensing switch 62 that can be a pressure switch or a vacuumswitch that is upstream of the control flap 52.

A. Inflatable Bladder

Referring in more detail to FIG. 3, the bladder 40 is constructed of ablank 64 of a material that can be formed and/or molded to maintain aseal of good integrity and which is a material that is preferablyflexible to enable the chambers of the blank to be easily inflated anddeflated while allowing the bladder chambers to resiliently deflectunder load. For defining inflatable chambers 46 and passages in thebladder 40, the blank 64 has a seal 66. To enhance the comfort of a seatoccupant, P (FIG. 18), one preferred embodiment of the bladder 40 ofthis invention has (a) a first pair of inflatable chambers 68 that areunderneath the thighs of the occupant when seated, and (b) a second pair70 of inflatable chambers that underlie the buttocks of the seatoccupant when seated. Preferably, the bladder 40 can be constructed withanother pair of inflatable chambers 72 that supports the both sides ofthe lower back or lumbar region of a seat occupant when seated. Ifdesired, the bladder 40 can be constructed without the third set ofinflatable chambers 72.

1. Thigh Chambers

Preferably, the first set of inflatable chambers 68 are suitably spacedapart such that they generally underlie the legs of a seat occupantadjacent the upper thigh region of the seat occupant. Preferably, tohelp control the behavior of each chamber 68 during inflation and whileunder load to prevent collapse and undesirable deformation or bulging ofeach chamber 68, each chamber 68 has a recessed relief peninsula 74which extends inwardly and which preferably partially divides eachchamber. Preferably, the relief peninsula 74 is an indention in bothsheets of the bladder 40 that are sealed together. Preferably, the seal66 extends inwardly into each chamber 68 for creating the reliefpeninsula 74 of each chamber.

Preferably, the first set of inflatable chambers 68 are constructed andarranged to provide cushioning support to the femur and ischium bones ofthe skeletal structure of a seat occupant while also providingcushioning support to the biceps and gluteus maximus muscles of the seatoccupant. During use of the bladder 40, as the first set of chambers 68are inflated, they increase pressure to the femur and biceps whiledecreasing pressure to the gluteus maximus and ischium. Conversely, aseach chamber 68 is deflated, pressure to the gluteus maximum and ischiumis preferably increased while pressure to the femur and biceps ispreferably decreased.

2. Buttocks Chambers

Preferably, the second set of inflatable chambers 70 are suitably spacedapart such that the chambers 70 provide support to the buttocks of aseat occupant. As is shown in FIGS. 3 & 4, each chamber 70 can have arelief indention 76, such as preferably for controlling the behavior ofeach chamber 70 during inflation and while under load to preventbulging, collapse and undesirable deformation of each chamber 70.Preferably, the relief indentation 76 of each buttocks chamber 70 isconstructed and arranged in a manner very similar to the reliefpeninsula 74 of each thigh chamber 68. If desired, each and everychamber of the bladder 40 may be constructed with such a reliefindention or relief peninsula for helping to control the behavior ofeach chamber during loading to help control bulging, collapse anddeformation of each chamber.

As is also depicted in FIG. 3, there can be a generally square shapedweb 78 of material joining the second set of chambers 70, if desired. Ifdesired, the web 78 of material can be removed or the bladder 40 can beconstructed without the web of material between the second set ofchambers 70.

Preferably, the second set of inflatable chambers 70 are constructed andarranged to provide cushioning support to the tuberosity of ischium andramus of ischium of the skeletal structure of a seat occupant while alsoproviding cushioning support to the gluteus maximus of the musclestructure of the seat occupant. During use of the bladder 40, as thesecond set of chambers 70 are inflated, the chambers 70 increasepressure to the tuberosity of ischium and gluteus maximus whiledecreasing pressure to the ramus of ischium. Conversely, as the chambers70 are deflated, each chamber 70 preferably increases pressure to theramus of ischium while decreasing pressure to the tuberosity of ischiumand gluteus maximus.

3. Lumbar Chambers

Preferably, the third set of inflatable chambers 72 are spaced apart sothat the chambers 72 are positioned adjacent the lumbar region of eachside of the lower back of a seat occupant. Preferably, the third set ofinflatable chambers 72 are constructed and arranged to provide supportto the posterior crest of ilium and sacral vertebra of the skeletalstructure of a seat occupant while also providing support to the erectorspinae and gluteus maximus muscles of the seat occupant. During use ofthe bladder 40, as the third set of chambers 72 is inflated, pressureupon the posterior crest of ilium and erector spinae of the seatoccupant is increased while pressure on the sacral vertebra and gluteusmaximus is decreased. Conversely, as each chamber 72 of the third set isdeflated, pressure on the sacral vertebra and gluteus maximus ispreferably increased while pressure on the posterior crest of ilium anderector spinae is preferably decreased.

4. Bladder Construction

To enable the first set of inflatable chambers 68 to be inflated anddeflated, the blank 64 has a gas passage 80 that extends from one of thechambers 68 to the control flap 52. Likewise, to enable the second setof inflatable chambers 70 to be inflated and deflated, the blank 64 hasa second gas passage 82 that extends from one of the chambers 70 to thecontrol flap 52. Additionally, the blank 64 also has a gas passage 84that extends from the control flap 52 to one of the inflatable chambersof the third set of inflatable chambers 72 to enable at least one of thechambers of the third set 72 to be inflated and deflated. Preferably,each gas passage 80, 82, and 84, has a flattened portion 86 forpermitting each passage to be bent, such as is shown in FIGS. 1 & 2,without obstructing gas flow through each passage.

Preferably, each chamber of each set of inflatable chambers cancommunicate gas to and from the other chamber of that same set ofchambers. As such, each chamber of the first set of chambers 68 canpreferably communicate gas to the other chamber of the first set 68through a connecting passage 88 that is also preferably defined by seal66. To enable the second set of chambers 70 to communicate gas betweeneach other, the seal 66 also preferably defines another connectingpassage 90. Preferably, the third set of chambers 72 can communicate gasbetween each other as a result of passage 84 having a first branch 92extending to one of the chambers and a second branch 94 extending to theother of the chambers.

FIG. 4 illustrates the bladder 40 carried by a seat occupant supportingsurface 98 of the seat 44 that preferably is a foam support cushion 100that makes up part of a seat cushion or a backrest of a seat. As isdepicted in FIG. 4, the bladder 40 is preferably received in a retainerpocket 96 in a foam support cushion 100 of the seat and has a seatcovering 102 which overlies both the cushion 100 and the bladder 40.

As is also shown in FIG. 4, the bladder 40 is constructed of a blank 64of material that preferably has a top layer 104 that is formed andjoined to a bottom layer 106 forming a bladder 40 that is preferably ofone-piece, unitary construction to facilitate seat assembly. Preferably,the seal 66 extends about the periphery of the top and bottom layers 104& 106 and about the periphery of each inflatable chamber and gas passageto help define each inflatable chamber and passage. As is shown moreclearly in FIG. 3, the control flap 52 is preferably also integrally apart of the blank 64 such that the control flap 52 and bladder 40 are ofone-piece and unitary construction to facilitate seat assembly.Preferably, the top and bottom layers 104 & 106 also form forcereceiving and cushioning surfaces 114 & 116 for each of the inflatablechambers 68, 70 & 72, in the region of each of the inflatable chambers68, 70 & 72.

The blank 64 can be vacuum formed to construct the bladder 40 of thisinvention. If vacuum formed, the blank 64 is preferably constructed of afirst sheet 108 that is formed and joined to a formed second sheet 110by the seal 66 forming a bladder 40 that is of one-piece, unitaryconstruction. If vacuum formed, the first sheet 108 preferably forms oneof the force receiving and cushioning surfaces 114 or 116 and the secondsheet 110 forms the other of the force receiving and cushioning surfaces114 or 116. For example, as is shown in FIG. 4, the first sheet 108forms the top surface 104 of the bladder 40 and the second sheet 110forms the bottom surface 106 of the bladder 40.

As is shown in FIGS. 3 & 4, representative of preferably each and everyinflatable chamber of a bladder 40 of this invention, inflatable chamber72 has force receiving and cushioning surfaces 114 & 116 of surfacearea, A (FIG. 3), and a sidewall 112 about its periphery that adjoinsthe force receiving and cushioning surfaces 114 & 116 of the chamber 72.Preferably, when no load is applied to an at least partially inflatedchamber 72, such as is depicted in FIG. 4, each sidewall 112 has aportion that (a) is generally perpendicular to at least one of thesupporting surfaces 114 or 116, (b) is generally perpendicular to atleast one of the layers 104 or 106 of the blank 40 in the region betweeninflatable chambers of the bladder 40, or (c) is generally perpendicularto a plane between the sheets 108 & 110 of the blank 64 in the chamberregion defined by the seal 66 for maximizing the inflated volume of eachinflatable chamber relative to the surface area of one of its forcereceiving and cushioning surfaces 114 or 116.

By maximizing the inflated volume of a chamber relative to the surfacearea of its force receiving and cushioning surfaces 114 or 116, eachinflatable chamber 68, 70 & 72 can advantageously be smaller in surfacearea while providing at least the same and preferably greater cushioningability as opposed to a chamber of conventional "pillow" constructionhaving a greater surface area. More particularly, this enables eachinflatable chamber of a bladder 40 of this invention to be able todeflect inwardly a greater distance before its top force receiving andcushioning surface 114 bottoms against its bottom force receiving andcushioning surface 116 because the top and bottom walls of each chamberare spaced further apart. As such, the bladder 40 of this invention isalso particularly well suited for vehicle seating that has a smallerseat occupant supporting surface, such as for example, a motorcycle seat44. Moreover, the cushioning ability of the foam support cushion 100 ofthe seat combined with inflatable chambers 68, 70 & 72, result in a seatthat provides a high degree of comfort to an occupant of the seat.Additionally, this inflatable chamber construction is also advantageousbecause it allows for a greater range of seat occupant adjustmentbecause its maximum inflated volume is greater relative to its surfacearea.

As is also depicted in phantom in FIG. 4, during operation of thebladder 40, the top surface 114 of each chamber 68, 70 & 72 canpreferably be expanded outwardly toward a maximum limit, M, to providesupport and cushioning to a seat occupant. Preferably, this maximumlimit of expansion, M, can be influenced by factors such as the gaspressure within the inflatable chamber, seat occupant weight, themaximum amount of stretch of the bladder material, vehicle seat loadingconditions, as well as other factors. Although the maximum limit ofexpansion, M, shown for each inflatable chamber 68, 70 & 72 depicted inFIG. 4 is approximately the same, the maximum limits of expansion forsome individual inflatable chambers can differ relative to otherinflatable chambers.

Alternatively, the blank 64 can be blow molded to form the bladder 40 ofthis invention. If blow molded, the blank 64 is preferably of one-pieceand at least partially tubular construction and is received in a moldhaving a three dimensional contour that is preferably complementary tothe desired final formed shape of each surface of the bladder 40. Ifdesired, an extrusion blow molding process may be used to construct thebladder 40 of this invention. If a blow molding process is used, theresultant bladder may lack an outwardly extending seal about itsperiphery, such as the outwardly extending seal shown in FIG. 4.Preferably, it will have a seal 66 between chambers and gas passages ofthe bladder 40 for defining the inflatable chambers and passages.

B. Integral Control Flap and Valve Assembly

1. First Control Flap Embodiment

FIGS. 5 through 7B illustrate a preferred embodiment of a control flapand valve assembly 120 for enabling each inflatable chamber 68, 70 & 72to be selectively inflated or deflated. Preferably, the control flap 52has an inlet port 122 for preferably gas tightly receiving the gassupply line 58 to enable gas to be admitted from the gas supply 60 (FIG.2) into one or more of the inflatable chambers 68, 70 & 72 of thebladder 40. The inlet port 122 preferably communicates gas to an inletpassage 123 and, thereafter, a manifold passage 124 in the control flap52 for enabling gas to be distributed to each of the chambers 68, 70 &72. Branching off from the manifold 124 are individual gas supplypassages 126 leading to the gas passages 80, 82 & 84 of the inflatablechambers 68, 70, & 72 for communicating gas to each of the chambers whenthe appropriate valve is opened. To enable gas to be exhausted from aninflatable chamber to deflate the chamber, each gas passage 126preferably also can communicate with an outlet passage 128. Preferably,each outlet passage 128 has an exhaust port 130, in the form of a slitor an opening, that enables gas to be exhausted from a chamber to theatmosphere during deflation of that chamber.

2. Pinch Valve Assembly

FIGS. 5 through 7B also illustrate in detail three pinch valveassemblies 132, each of which cooperate with the control flap 52 toenable a seat occupant to (a) selectively admit gas into one or more ofthe inflatable chambers 68, 70 & 72 to inflate the desired chamber, (b)selectively exhaust gas from one or more of the chambers 68, 70 & 72 todeflate the desired chamber, or (c) retain gas in one or more of theinflatable chambers 68, 70 & 72 to maintain a desired amount of gas inone or more of the chambers 68, 70 & 72 to achieve a desired level ofsupport or cushioning for the seat occupant. Preferably, the assembly120 has a valve 155 for controlling gas flow to and from the thighchambers 68, a valve 156 for controlling gas flow to and from thebuttocks chambers 70, and another valve 157 for controlling gas flow toand from the lumbar chambers 72.

As is shown in FIG. 6, each pinch valve 132 can be placed in a gasretaining position, where both the supply passage 126 and outlet passage128 leading to a particular inflatable chamber of the bladder 40 arepinched preferably closed to retain gas within that chamber.Additionally, as is shown in FIG. 7A, each valve 132 can also be urgedto a gas admitting position where the supply passage 126 is opened andthe outlet passage 128 is pinched closed permitting gas from the supply60 to inflate the desired chamber. Finally, as is shown in FIG. 7B, eachvalve 132 can be urged to a gas exhausting position where the outletpassage 128 is opened and the supply passage 126 is pinched closed fordeflating the chamber by exhausting gas from the chamber out the exhaustport. Preferably, each valve 132 is biased to a gas retaining positionand must be manually urged by a seat occupant to either the gasadmitting position or the gas exhausting position.

As is shown more clearly in FIG. 5, the valve assembly 132 has a valvebody 134 that is preferably generally T-shaped. The valve body 134 has astem 136 that is preferably received through an opening or slit 138 inthe control flap 52 adjacent the gas supply passage 126 and outletpassage 128 of an inflatable chamber. Preferably, the stem 136 is ofgenerally square or generally rectangular cross section to facilitateits insertion through the control flap mounting slit 138. Alternatively,the valve stem 136 could also be of generally round cross section, suchas if it is desired to have an end of the stem 136 to be threaded toreceive a threaded valve cap or button.

At one end of the stem 136 are a pair of outwardly extending legs 140 &142 which bear against control flap gas passages 126 and 128 when thevalve 132 is in the gas retaining position, such as is shown in FIG. 6.To facilitate pinching of a gas passage, the end of each leg 140 & 142of the valve body 134 preferably has an outwardly protruding boss 144that bears directly against the gas passage when the valve 132 ispinching the passage closed.

Preferably, the valve body 134 is constructed of a metal, such aspreferably steel, aluminum, titanium, copper, a stainless steel,magnesium, an alloy of one of these metals, or another suitable metal.Alternatively, the valve 134 body could be constructed of a plastic, acomposite, another polymeric material, or a synthetic material. Forexample, the valve body 134 could also be constructed of a nylon, glassfilled nylon, a carbon fiber composite, LEXAN, polycarbonate, athermoplastic material, or even a thermosettable plastic, such asbakelite.

At the other end of the stem 136, the valve 132 has a cap 146 receivedon the end of the valve stem 136, preferably also for helping to retainthe valve 132 when its stem 136 is inserted through the control flapslit 138 thereby mounting it to the control flap 52. Preferably, the cap146 is pressed onto the end of the valve stem 136. If desired, the cap146 could also be welded or adhesively fastened to the valve stem 136.If desired, if desired, the cap 146 can be threaded onto a threaded endof the stem 136 for securing the cap 146 to the valve 132. Additionally,although a cap 146 of generally round construction is depicted in FIGS.5 through 7B, the cap 146 could be of square or generally rectangularconstruction, if desired.

To urge the legs 140 & 142 of the valve body 134 against the gaspassages 126 & 128 when the valve 132 is in the gas retaining position(FIG. 6), the valve 132 has a spring 148. Preferably the spring 148 islocated on the stem 136 of the valve 132 between the cap 146 and controlflap 52 for urging or biasing the valve 132 toward its gas retainingposition. Preferably, the spring 148 urges the valve 132 toward its gasretaining position for returning the valve 132 to the gas retainingposition when the seat occupant has released the valve 132 and also forretaining the valve 132 in the gas retaining position when the seatoccupant is not engaging the valve 132. Preferably, the spring 148 is acoil spring having a spring constant or spring rate sufficiently largeso as to draw the valve 132 against the desired gas passage of thecontrol flap 52 with enough force to pinch the passage closed such thata gas tight seal in that passage is preferably created at the pinchpoint.

To shield the control flap 52 from the environment and provide supportto each valve 132 to enable each valve 132 to be pivoted between its gasretaining (FIG. 6), gas admitting (FIG. 7A), and gas exhausting (FIG.7B) positions, there preferably is a bezel or cover panel 150 (shown inphantom in FIG. 5) between the outer surface of the control flap 52 andthe valve spring 148. Preferably, the control flap cover panel 150 isconstructed of a resilient and relatively stiff material such as ametal, a plastic, or wood for enabling it to provide good support toeach valve 132 during use and operation of the valve 132. Preferably,the panel 150 can be a bezel that is sewn directly to the seat covering102 of the seat 42 for positioning and anchoring the control flap 52 ofthe bladder 40 when seat assembly is completed.

To facilitate the pinching of each gas passage of the control flap 52and to assist in properly locating each valve leg 140 & 142 relative tothe desired gas passage, the control flap cover panel 150 preferably hasa valve seat 152 overlying the supply passage 126 and another valve seat154 overlying the exhaust passage 128. Preferably, each valve seat 152 &154 is a through opening in the cover panel 150. If desired, each valveseat 152 & 154 can simply be an indention, recess, or pocket in theunderside of the panel 150 to enable each valve 132 to better seal thegas passage it is pinching against. Preferably, the periphery of eachvalve seat opening 152 & 154 is substantially complementary with theshape of the boss 144 on each valve leg to help maximize sealing of thegas passage. For example, each valve seat opening 152 & 154 or indentioncan have a square, round, or preferably generally rectangular shape forfacilitating sealing of the passage when the boss 144 of a valve legbears against a gas passage, such as when the valve 132 is in the gasretaining position depicted in FIG. 6.

In use and operation of a valve 132 shown in FIGS. 5 through 7B, whennot engaged by a seat occupant, the valve 132 preferably remains in thegas retaining position shown in FIG. 6, pinching both the supply passage126 and outlet passage 128 closed thereby causing gas already inside theinflatable chamber of the bladder 40 associated with that valve 132 toremain in that chamber. As is also illustrated in FIG. 6, when the valve132 is in the gas retaining position, the boss 144 of each valve leg 140& 142 bears against gas passages 126 & 128 and preferably seats in valveseat openings 152 & 154.

If it is desired for gas to be admitted into a gas chamber to inflatethe chamber, such as chambers 68, 70 or 72, the valve 132 of the desiredset of inflatable chambers is pivoted clockwise, such as is depicted bythe direction indicating arrow in FIG. 7A, causing its valve leg 140 tocontinue pinching the outlet passage 128 closed while moving its othervalve leg 142 away from the supply passage 126, opening the passage 126,and thereby permitting gas flow through the passage 126.

If it is desired to deflate a chamber, the desired valve 132 can bepivoted in a counterclockwise direction, such as is depicted by thearrow in FIG. 7B, to cause its valve leg 142 to pinch the supply passage126 while moving its other leg 140 away from the outlet passage 128,thereby permitting gas to flow through the passage 128 and out theexhaust port 130. When released, the valve 132 preferably returns to itsgas retaining position and remains in the gas retaining position untilfurther engaged by an operator of the control flap 52 that typicallywill be the seat occupant.

3. Second Control Flap Embodiment and Pneumatic Valve Arrangement

FIG. 8 illustrates a second preferred embodiment of a control flap andvalve assembly 120' for enabling each inflatable chamber 68, 70 & 72 ofthe bladder 40 to be selectively inflated or deflated. Preferably, thecontrol flap 52' has a series of fittings or nipples thatcomplementarily and airtightly mate with a series of fittings or nipplesof a pneumatic valve assembly 160 to enable gas to be (a) retained in achamber of the bladder 40, (b) admitted into the chamber, or (c)exhausted from the chamber.

As is shown in FIG. 8, the control flap 52' can be constructed andarranged such that there is a fitting or nipple 162 at the end of eachgas passage 54, each for enabling connection to a single pneumatic valveor a pneumatic valve 164 of the multiple pneumatic valve assembly 160.To connect each valve 164 to a supply nipple 162, each valve 164preferably has a complementary fitting or nipple 166 that sealinglymates with the supply nipple 162. As such, to enable gas to be admittedor exhausted from each chamber, gas passages 80, 82 & 84 each havefitting or nipple 162 for receiving the complementary fitting or nipple166 of each valve 164. To enable gas to be exhausted to deflate achamber, each valve 164 can be constructed with an exhaust port 168. Tofacilitate mounting of the valves 164 to the control flap 52', there maybe a cover panel (not shown) between the control flap 52' and the valves164.

Referring additionally to FIG. 9, each valve 164 can be of rocker-typeconstruction having a housing 170 with a button 172 that can be pivotedin one direction to admit gas into a chamber 68, 70 or 72 of the bladder40 and in another direction to exhaust gas from a chamber. Preferably,the button 172 of each valve is biased to a gas retaining position whenreleased by a seat occupant or not engaged by a seat occupant, such asis depicted in FIG. 9. To admit gas from the gas supply 60, the valveassembly 160 has an inlet port 174 connected to the gas supply line 58.

If desired, the bladder control flap 52 or 52' can also be modified toaccommodate a valve of the type disclosed in Foiling, U.S. Pat. No.3,652,126, to enable individual bladder chambers 68, 70 and/or 72 to beselectively and controllably inflated and deflated by a seat occupant.If such a valve is used, the control flap 52 or 52' can preferably beconstructed with integral nipples for quick and easy connection of eachsuch valve to the control flap.

4. Third Control Flap Embodiment and Pneumatic Valve Arrangement

FIGS. 10 & 11 illustrate a third preferred embodiment of a control flapand valve assembly 120" for enabling each inflatable chamber 68, 70 & 72of the bladder 40 to be selectively inflated or deflated. The controlflap 52" extends from the bladder 40 and comprises a pair of urethanesheets 108 & 110 that have a split line 111 where the sheets 108 & 110are separable from each other for exposing gas passages 80, 82, & 84 toreceive a pneumatic valve assembly 160'.

In assembly, the control flap sheets 108 & 110 are urged apart to exposeopenings to gas passages 80, 82 & 84 so that the nipples 166 of thevalve assembly 160' can be inserted into the gas passage openings. Afterthe nipples 166 of the valve assembly 160' are inserted into the gaspassage openings, the sheets 108 & 110 are released. Upon release, thesheets 108 & 110 tend to want to contract to their original positioncausing the sheets 108 & 110 in the area of the gas passage openings tocontract around the valve nipples 166 to securely mount the valveassembly 160' to the control flap 52" in a gas tight fashion, as isdepicted in FIG. 11.

C. Gas Supply

Referring to FIGS. 2 & 3, the gas supply 60 has a gas pump 61 (shown inFIG. 2 in phantom) for supplying gas under pressure to one or moreinflatable chambers 68, 70 or 72 of the bladder 40 upon demand by a seatoccupant. To provide a charge of pressurized gas to facilitate quicklyinflating one or more chambers 68, 70 or 72 of the bladder 40, the gaspump 61 is preferably received in a reservoir 63. To cause the pump 61to provide gas under pressure, the pump 61 is preferably incommunication with pressure sensor 62 that is a switch capable ofcontrolling pump operation.

Preferably, the gas pump 61 is a compressor that charges the reservoir63 with gas from a gas source exterior of the reservoir 63 to enable gasto be provided on demand to inflate the bladder chambers. Preferably,the compressor 61 is an air compressor that transfers air from outsidethe reservoir 63 into the reservoir 63. To enable air to be drawn fromoutside the reservoir 63 and pumped into the reservoir 63, thecompressor 61 preferably has an inlet 75 (FIG. 16A) that extends outsideof the reservoir 63.

Preferably, the gas used to charge the reservoir 63 and inflate thebladder 40 is air. If desired, another gas can be used to charge thereservoir 63, such as for example, carbon dioxide, helium, or anothersuitable gas. If desired, a suitable fluid can also be used to inflateone or more chambers of the bladder 40.

Preferably, the compressor 61 is electrically powered by a suitablepower source (not shown) such as a six or twelve volt vehicle powersupply, an alternating current power supply, a direct current powersupply, electricity from a generator or alternator of a vehicle, as wellas a power supply that can consist of a battery or series of batteriescapable of providing sufficient electrical energy to energize and powerthe compressor 61. For example, a battery such as a lithium ion, nickelhydride, lead acid, or another type of battery, that preferably isrechargeable, can be used to power the compressor 61, thereby alsoenabling the bladder 40 of this invention to be used for seatingapplications other than vehicle seating.

The reservoir 63 preferably is a sealed inflatable bag that has anoutlet 65 connected to the gas supply line 58 for enabling the bag 63,when charged with gas under pressure, to instantly provide a supply ofgas to inflate a chamber 46 of the bladder 40 when a valve 56 of thebladder 40 is moved to its gas admitting position. Preferably, thereservoir bag 63 holds a charge of pressurized gas sufficient to begininflating one or more bladder chambers 46 when a valve 56 is moved toits gas admitting position without requiring the compressor 61 tooperate, preferably until the gas pressure within the reservoir bag 63drops below a predetermined threshold pressure level. Advantageously,this enables gas to be immediately supplied on demand to the bladder 40without having to wait for the compressor 61 to energize and beginsupplying gas to the bladder 40.

Preferably, the reservoir bag 63 is constructed of a synthetic, plastic,or polymeric material, such as preferably a urethane, and is preferablyof gas tight construction to enable the bag 63 to retain a charge of gasat a pressure greater than ambient or atmospheric pressure substantiallywithout experiencing a detrimental amount of leakage from the bag 63.Preferably, the bag 63 can be blow molded with an opening of sufficientsize for enabling the compressor 61 to be placed inside the bag 63. Ifdesired, the bag 63 can be constructed from a tubular blank that is gastightly sealed at both ends. If desired, the bag 63 can be sealed byheat sealing, ultrasonically welding, using an adhesive or by anothertype of sealing process to create a seal that is preferably gas tight topermit the bag 63 to be pressurized during operation.

The reservoir bag 63 can hold a charge of gas at a pressure of at leasttwelve pounds per square inch. Preferably, the reservoir bag 63 isconstructed to hold a charge of air at a pressure of at least aboutfifteen pounds per square inch to enable air from the bag 63 to beimmediately supplied to the bladder 40 upon demand by a seat occupant.

Preferably, the pressure sensing switch 62 is in communication with thereservoir bag 63 to sense the pressure of the air within the bag 63. Asis shown in FIG. 2, the pressure switch 62 can be connected by agenerally T-shaped fitting 67 to the supply line 58, and is preferablylocated downstream of the reservoir bag 63 and upstream of the valves 56of the control flap 52. If it is desired to eliminate the use of aT-shaped fitting 67, the pressure switch 62 can directly communicatewith the gas in the reservoir bag 63, as is depicted in phantom in FIG.16A, to sense pressure within the bag 63 as well as upstream of thevalving and control flap 52. The pressure sensing switch 62 preferablyessentially functions as an on-off switch for the compressor 61,activating the compressor 61 when pressure in the reservoir bag 63 hasdropped below the predetermined threshold pressure level. To controloperation of the compressor 61, the pressure switch 62 is connected tothe compressor 61 by at least one electrical wire 69, such as is shownin FIG. 2. Another wire 71 is preferably connected to a power source(not shown). As is also depicted in FIG. 2, the compressor 61 has atleast one electrical wire 73 also leading to the power source.Alternatively, a vacuum switch 77 (FIG. 16B) received inside thereservoir bag 63 could also be used to sense pressure within thereservoir bag 63 to control operation of the compressor 61.

Preferably, the threshold pressure, P, of the pressure switch 62 isabout twelve pounds per square inch. Preferably, the switch 62 has alower threshold pressure, P₁, and an upper threshold pressure, P₂, fordetermining when to energize the compressor 61 and for determining whento deenergize the compressor 61. Preferably, the lower thresholdpressure, P₂, determines when the pressure switch 62 energizes thecompressor 61 to recharge the reservoir 63 with additional air.Preferably, the upper threshold pressure, P₂, determines when todeenergize the compressor 61, preferably when the reservoir 63 has beenfully recharged. For the motorcycle seat bladder 40 and gas supply 60depicted in FIGS. 1 through 4, the lower threshold pressure, P₁, ispreferably about twelve pounds per square inch to energize thecompressor 61 and the upper threshold pressure, P₂, is preferably abouteighteen pounds per square inch to deenergize the compressor 61.

If desired, the lower threshold pressure, P₁, can be less or more thantwelve pounds per square inch and the upper threshold pressure, P₂,could be greater or more than eighteen pounds. For other seatingapplications and bladder configurations, routine research andexperimentation may be required to determine an upper thresholdpressure, P₂, or range of pressures and a lower threshold pressure, P₁,or range of pressures which facilitate operation of the gas supply 60 toenable it to supply a sufficient amount of gas to the bladder 40 ondemand by a seat occupant. A vacuum switch 77 (FIG. 16B) can also beused in this manner to control compressor operation.

A preferred embodiment of a gas supply 60 and reservoir bag 63 is shownin FIG. 16B. The gas supply has a compressor 61 received inside the bagwith an inlet line 75 extending into the bag 63 for enabling thecompressor 61 to draw air from outside the bag 63 into the bag 63.Although not shown, the compressor 61 has a discharge within the bag 63that enables the compressor 61 to expel outside air that has beenpressurized by the compressor 61 into the bag 63.

To control operation of the compressor 61, a vacuum switch 77 is alsoreceived inside the bag 63 and is in electrical communication with thecompressor 61 for sensing the pressure within the bag 63 and energizingor deenergizing the compressor 61 depending upon the sensed pressure. Toprovide a reference for the vacuum switch 77, the switch 77 has areference port 79 that is in communication with the atmosphere outsidethe bag 63. Preferably, the reference port 79 is in communication withthe ambient pressure for providing a pressure reference for operation ofthe switch 77.

To enable operation of the compressor, the switch 77 and compressor 61are connected together by electrical wires. Preferably, a pair of wiresfrom an electrical power source communicate both with the switch 77 andcompressor 61. So that the switch 77 can control operation of thecompressor 61, the switch 77 is preferably wired in series with thecompressor 61.

A preferred construction of the reservoir bag 63 is also shown in FIG.16B. The bag 63 is preferably constructed of two sheets 81 of urethanejoined together by a seal 83 about its periphery to form a bag 63 thatis gas tight and which can hold gas under pressure preferably withoutleaking. To connect the gas supply line 58 to the bag 63, there is abreak in the seal 83 forming an outlet 65. Preferably, the size of theoutlet opening 65 is slightly smaller than the gas supply line 58 toprovide a gas tight friction fit between the line 58 and outlet 65. Ifdesired, a sealant or an adhesive can be used to better provide a gastight seal between the gas supply line 58 and the outlet 65 of thereservoir bag 63.

To enable electrical wiring to be introduced into the bag 63, the seal83 has another break forming a conduit 85 for the wires. Preferably, theconduit 85 gas tightly seals around the wires for preventing leakagefrom the bag 63. If desired, a sealant or an adhesive can be used tobetter provide a gas tight seal between the wires and the conduit 85 ofthe reservoir bag 63.

To enable the reference port 79 of the switch 77 to communicate with theatmosphere outside of the bag 63, the seal 83 has a break forming areference port conduit 87. Preferably, the conduit 87 gas tightly sealsaround the reference port 79 of the switch 77 to prevent leakage fromthe bag 63.

To facilitate drawing gas into the reservoir bag 63, the seal 83 hasanother break that forms an inlet opening 89 for receiving therethroughthe compressor inlet line 75. Preferably, the inlet 89 gas tightly sealsaround the compressor inlet line 75 to prevent leakage.

II. METHOD OF BLADDER MANUFACTURE

FIGS. 12 through 14 illustrate a vacuum forming press 180 for depictinga method of making a bladder 40 of this invention. In practicing amethod of making a bladder 40 of this invention, each sheet 108 & 110 isfirst preheated to make it more pliable for forming. After preheating,each sheet 108 & 110 is drawn against a three dimensionally contouredmold, preferably by application of a vacuum, to form the inflatablechambers and gas passages of the bladder 40. During the formingoperation, the molds are brought together to form a seal 66 between thesheets 108 & 110, joining the sheets 108 & 110 together to form thebladder 40 while also defining the boundaries of each inflatable chamberand gas passage.

A. Apparatus for Preheating, Forming, and Molding

As is shown in FIG. 12, the vacuum forming press 180 has a base 182which can rest on a floor or supporting surface 184 of a moldingfacility, manufacturing plant, or the like. To enable a bladder 40 to bevacuum formed, the press 180 has a lower female vacuum mold 186 cardedby the base 182 and an upper female vacuum mold 188 secured to a pressram 190 that is carried by an arm 192 that is, in turn, supported by thebase 182.

To preheat a sheet 108 or 110 of a blank 64 which is to form the bladder40 after vacuum forming and molding takes place, the upper sheet 108 ofthe blank 64 is placed upon a preheating table 194. Preferably, thepreheating table 194 has an upper heating surface 196 for preheating thetop sheet 108 of the bladder blank 64 and a lower heating surface 198for preheating a bottom sheet 110 of the blank 64, all in preparationfor vacuum forming. Before preheating occurs, the lower sheet 110 of theblank 64 is preferably placed on a platter 200 that is preferablycarried by the base 182 of the press 180 or which rests upon the ground184.

To enable the bottom sheet 110 to be retained against the lower heatingsurface 198 of the preheating table 194, the table 194 preferably alsois a vacuum table that is connected by a vacuum line 202 to a vacuumsource (not shown), such as a vacuum pump, an eductor, an ejector, aventuri, or another device capable of producing a vacuum. Preferably,any vacuum created within the table 194 is also communicated to both theupper heating surface 196 and the lower heating surface 198 for drawingeach sheet 108 & 110 of the blank 64 into tight intimate contact with aheating surface to maximize heat transfer from each heating surface toeach sheet. Preferably, each heating surface 196 & 198 has a pluralityof perforations or holes for enabling vacuum to be communicated fromwithin the table 194 to each sheet 108 & 110, to retain each sheet 108 &110 against a heating surface 196 or 198.

Preferably, each heating surface 196 & 198 is a contact heater fortransferring heat from the heating surface to a sheet of the blank 64primarily through contact between the sheet and heating surface.Preferably, each heating surface 196 & 198 is comprised of a pluralityof strip heaters which are electrically heated to preheat the sheets 108& 110 of the blank 64 for vacuum forming. Preferably, resistance orinductive heating is used to heat the strip heaters and the amount ofheat generated by the strip heater can preferably be selectivelycontrolled by an operator of the press 180 to selectively andcontrollably preheat each sheet 108 & 110 of the blank 64 to atemperature that facilitates vacuum forming. Preferably, each stripheater is a resistive strip heater constructed of copper or a copperalloy. Preferably, the amount of heat generated by the top heatingsurface 196 can be selectively independently controlled apart from theamount of heat generated by the bottom heating surface 198 to enableboth sheets to be heated to approximately the same temperature beforeforming and to prevent overheating of the top sheet 108.

Preferably, the surface of each heating surface 196 & 198 that directlycontacts a sheet 108 & 110 of the bladder blank 64 is coated with ananti-stick or friction reducing coating for preventing the sheet of theblank from adhering or sticking to the preheating table 194. Preferably,each surface 196 & 198 is coated with an anti-stick or friction reducingmaterial, such as TEFLON, and which can be in the form of a tape, film,or powder, to prevent each sheet 108 & 110 from sticking to the table194, particularly after being heated during preheating.

Preferably, heat generated by a heating surface 196 or 198 can beselectively adjusted and controlled such as by a variable resistor oranother type of heating control. If desired, the heating surface can bein communication with one or more temperature sensors, such as one ormore thermocouples, for enabling the temperature of a heating surface196 and/or 198 or a sheet 108 and/or 110 of the blank 64 to be sensed.If desired, temperature information can be utilized by electroniccircuitry to controllably heat each sheet 108 & 110 of the blank 64 to adesired temperature for vacuum forming and to maintain each sheet 108 &110 at the desired temperature for a desired period of time, ifnecessary. If desired, a blank 64 for constructing a bladder 40 of thisinvention could be preheated by another type of contact heater oranother method of heat transfer, such as, for example, a type of radiantor convective heating.

To enable the bottom sheet 110 to be transferred from the platter 200 tothe lower heating surface 198 of the preheating table 194, the platter200 preferably can be moved upwardly toward the lower heating surface198. Preferably, a vacuum is applied to the lower heating surface 198before or when transferring the sheet 110 to enable the sheet 110 to bepicked up from the platter 200 and cause the sheet 110 to be retainedagainst the lower heating surface 198. Alternatively, the preheatingtable 194 can be constructed and arranged so as to be movable downwardlytoward the platter 200 to transfer the sheet 110 from the platter 200 tothe lower heating surface 198.

To enable the sheets 108 & 110 to be transported to the vacuum molds 186& 188, the preheating table 194 is mounted by guide arms 204 to rails206 carried by the press base 182 enabling the table 194 to slide on therails 206 toward the molds 186 & 188 until it is preferably positionedadjacent to and between the molds 186 & 188. Preferably, each rail 206is mounted by angle irons 208 & 210 to the base 182 adjacent one end andby angle irons (not shown) carried by the base 182 adjacent the otherend. So that the table 194 will "float" or simply be displaceddownwardly when clamped between the vacuum molds 186 & 188 to facilitatepress damping of the table 194 between the molds 186 & 188, each end ofeach rail 206 is preferably carried by a spring 212 on one of the angleirons. To enable the table 194 to "float", the upper angle iron 208 maynot need to be attached to the base 182 of the press 180.

To enable the upper mold 188 to be brought towards the lower mold 186 toclamp the table 194 between the molds 186 & 188 and thereafter to clampthe sheets 108 & 110 of the blank 64 between the molds 186 & 188, thepress ram 190 preferably has a reciprocable piston (not shown) which canbe extended downwardly to preferably move the upper mold 188 towards thelower mold 186. Preferably, the press ram 190 is a hydraulic orpneumatic cylinder that has a piston 191 which can be controllablyextended to move the upper mold 188 relative to the lower mold 186. Ifdesired, a press ram 190 can also be used to move the lower mold 186towards the upper mold 188. In fact, a combination of upper and lowerpress rams can be used to bring the upper and lower molds toward eachother, if desired.

To maintain accurate location of the lower mold 186 relative to theupper mold 188 when moving one of the molds relative to the other of themolds, such as during press operation, the press base 182 preferably hasguide pins 214 that extend upwardly from the region of the lower mold186 and which are received in complementary locator bores 216 in theupper mold 188. By maintaining accurate location of the upper mold 188relative to the lower mold 186, and vice versa, during forming, itinsures accurate placement of the seal 66 of the bladder 40 so that allof the chambers 68, 70 & 72 and gas passages of the bladder 40, andintegral control flap 52, are properly formed, accurately located andwell defined.

To further facilitate maintaining accurate location of the molds 186 &188 relative to each other when they are clamped directly against eachother, such as is shown in FIG. 14, one of the molds preferably has anotch 250 and the other of the molds preferably has an outwardlyprojecting locator 252 of complementary construction that engages thenotch 250. When the locator 252 of one mold 188 is received in thelocator notch 250 of the other mold 186, it preferably also clamps thesheets 108 & 110 about their periphery to create a vacuum seal about theperiphery of the molds 186 & 188 to maintain a vacuum of good integrityduring forming and molding.

To introduce a vacuum to the lower mold 186 during forming of the bottomsheet 110, the lower mold 186 has a vacuum fitting 218 connected to avacuum hose 220 that is attached to a vacuum source (not shown). Tointroduce a vacuum to the upper mold 188 during forming of the top sheet108, the upper mold 188 has a vacuum fitting 222 connected to a vacuumhose 224 that is also attached to a vacuum source (not shown). Ifdesired, the vacuum source which provides a vacuum to the preheatingtable 194 may also be used as a vacuum source for one or both molds 186& 188. Although the top sheet 108 of the bladder 40 has been heretoforedepicted as being formed by the upper mold 188 and the bottom sheet 110of the bladder 40 as being formed by the lower mold 186, it should bepointed out that the top sheet 108 of the bladder 40 can also be formedby the lower mold 186 and the bottom sheet 110 formed by the upper mold188 since both molds 186 & 188 have substantially similar and preferablyvirtually identical three dimensional contours.

Referring to FIGS. 13 & 14, the lower mold 186 has a three dimensionallycontoured surface 230 for forming and molding a sheet which issubstantially similar and preferably virtually identical to the threedimensionally contoured surface 230 (FIG. 14) of the upper mold 188. Asis shown more clearly in FIG. 13, the three dimensionally contouredmolding surface 230 has an upraised wall 232 about its periphery that ispreferably flattened to provide a land 233 for mating against acomplementary land 233 of the other mold. This upraised wall 232 notonly prevents vacuum leakage from inside the periphery defined by thewall 232 when the molds 186 & 188 are pressed against each other duringforming of the bladder 40, it also preferably defines at least part ofthe seal 66 of the bladder 40 when forming and molding of the sheets 108& 110 are completed.

For forming the inflatable chambers 68, 70 & 72 of the bladder 40 shownin FIG. 1, the molding surface 230 respectively has a first pair ofrecessed inflatable chamber forming cavities 234, a second pair ofrecessed chamber forming cavities 236, and a third pair of recessedchamber forming cavities 238. To form gas passages in the bladder, suchas passages 80, 82, 84, 88, 90, 92 & 94, the molding surface 230 hasrecessed channels 240 of preferably generally semi-hemispherical crosssection. Likewise, gas passages 124, 126 & 128 in the control flap 52are formed by similarly contoured and recessed channels 242 in a controlflap portion 244 of the molding surface 230.

Preferably, as is shown in FIGS. 13 & 14, each mold 186 & 188 hassidewalls 245 adjoining the recessed inflatable chamber forming cavities234, 236 & 238 and the upraised wall portion 232, with the sidewalls 245having a portion that is preferably substantially perpendicular toeither (1) the exterior surface of the upraised wall 232 or (2) thesheet contacting surface of a recessed chamber forming cavity 234, 236,or 238, for forming sidewalls 112 of the bladder 40 that each have aportion generally perpendicular for maximizing the inflatable volume ofeach chamber 68, 70 & 72 relative to its surface area.

To provide the indented relief peninsula 74 in each thigh supportingchamber 68, the mold surface 230 has an upraised molding peninsula 246extending inwardly into each recessed thigh chamber forming cavity 234.If it is desired for the seal 66 to coincide with each relief peninsula76 of each thigh supporting chamber 68, the molding peninsula 246 of onemold 186 or 188 can mate with the molding peninsula 246 of the othermold 186 or 188 to cause the relief peninsula 74 of one sheet 108 or 110to be joined or sealed to the relief peninsula 74 of the other sheet 108or 110, for a given chamber 68. Likewise, to form the relief indentions76 of the buttocks chambers 70, one or both molds can have an upwardlyprojecting protrusion 248. If it is desired that the relief indentions76 of each pair of chamber top and bottom walls are to be sealedtogether, the protrusions 248 of one of the molds preferably extendssufficiently outwardly such that it mates against the protrusions 248 ofthe other of the molds during forming.

To draw each sheet against the three dimensionally contoured moldsurface 230 during forming and molding, each mold preferably has aplurality of perforations or bores in the mold 186 & 188 thatcommunicate respectively with vacuum hoses 220 & 224 to enable a vacuumto be created within each mold 186 & 188. Preferably, the size, spacingand density of the vacuum communicating bores or perforations of eachmold 186 & 188 are optimized to draw each sheet 108 & 110 of the bladderblank 64 into tight intimate contact with a molding surface 230 duringforming and molding.

B. Preheating

Referring to FIG. 12, during preheating of the bladder blank 64, avacuum is preferably applied to the preheating table 194 to draw the topsheet 108 against the upper heating surface 196 of the table 194. Tocause the lower sheet 110 to be preheated, the platter 200 carrying thesheet 110 is preferably raised upwardly toward the lower heating surface198 of the table 194 until the vacuum draws the sheet 110 against thelower heating surface 198 of the table 194. Preferably, the vacuumapplied to the heating table 194 is sufficient to draw each sheet 108 &110 into tight intimate contact with the heating surfaces 196 & 198 ofthe table 194. Preferably, a vacuum of at least eighteen inches ofmercury is applied to the vacuum table 194 to suitably draw the sheets108 & 110 against the heating surfaces 196 & 198.

Heat is applied to each sheet 108 & 110 until each sheet reaches atemperature that makes it suitably pliable for forming and molding. Forexample, for sheets 108 & 110 constructed of urethane having a thicknessof approximately fifteen-thousandths of an inch, the preheating table194 preferably applies sufficient heat to the top sheet 108 and thebottom sheet 110 until both sheets 108 & 110 reach a temperature that isgreater than about 150° Fahrenheit and which is preferably between about305° Fahrenheit and 315° Fahrenheit. Preferably, heating the sheets 108& 110 until they reach the desired temperature also facilitates moldingby enabling the sheets 108 & 110 to be joined to form the seal 66 of thebladder 40 by simply applying enough pressure against each sheet 108 &110 in the seal region, preferably without requiring any adhesivebetween the sheets 108 & 110. For sheets constructed of a urethanehaving different thicknesses, routine testing and experimentation may beperformed to determine the desired amount of heat to apply to each sheetto heat it to the desired temperature to enhance and preferably maximizeforming and molding of each sheet in making a bladder 40 of thisinvention.

To maximize formability of each sheet 108 & 110, it may be desirable tomaintain each sheet 108 & 110 at the desired preheat temperature for apredetermined period of time. Preferably, however, the top sheet 108 canbe transferred to the upper mold 188 and the bottom sheet 110transferred to the lower mold 186 after each sheet 108 & 110 reaches thedesired preheat temperature. Preferably, each sheet 108 & 110 can betransferred to a mold for forming upon reaching the desired preheattemperature.

In a preferred embodiment of the bladder 40, such as the embodimentshown in FIG. 1, each sheet 108 & 110 is constructed of a relativelyflexible and formable urethane having a thickness of approximatelyfifteen-thousandths of an inch and is heated to a temperature of betweenabout 305° Fahrenheit and 315° Fahrenheit in preparation for forming andmolding. If desired, a urethane of another thickness could be used.Additionally, urethane sheets of two different thicknesses could also beused, such as if it is desired, for example, to construct the bladder 40having its bottom sheet 110 thicker than the top sheet 108 to enableforces applied to the bladder 40 during use to be more uniformlydistributed and transferred to the foam support cushion 100 (FIG. 4) ofa seat.

If desired, the sheets 108 & 110 can also be constructed of polyvinylchloride, ethylene vinyl acetate, polyethylene, or another resilient,relatively flexible, formable, and moldable material that can be formedand molded into a bladder 40 of this invention having a seal 66 of goodintegrity and which is gas tight. Preferably, these materials can alsobe used to construct the bladder 40 if the blank 64 is constructed ofonly a single sheet or tubular piece of material.

C. Forming

When preheating has been completed, each sheet 108 & 110 is transferredto a mold 186 & 188 where the sheets are three dimensionally formed toimpart to the sheets the desired three dimensional bladder shape. Toform the sheets 108 & 110, the preheating table 194 is brought betweenthe upper mold 188 and lower mold 186, preferably by moving it along therails 206. In preparation for transferring the top sheet 108 to theupper mold 188 and the bottom sheet 110 to the lower mold 186, the ram190 is actuated, extending its piston 191 outwardly. As the piston 191is extended, the upper mold 188 is brought downwardly to bear againstthe top sheet 108 and upper heating surface 196 of the preheating table194, also urging the table 194 downwardly against the lower mold 186.

To transfer the top sheet 108 to the upper mold 188 and the bottom sheet110 to the lower mold 186, a vacuum is applied preferably both to thelower mold 186 and upper mold 188. Preferably, during transfer of thesheets 108 & 110 to the molds 186 & 188, the vacuum to the preheatingtable 194 is cut off and pressure within the table 194 is allowed torise towards ambient or atmospheric pressure levels. In fact, tofacilitate transfer of the sheets 108 & 110, vacuum to the table 194 canbe cut off and the table 194 can preferably slightly positivelypressurized to prevent the sheets 108 & 110 from adhering to the table194 during the transfer. Preferably, the table 194 can be positivelypressurized to a pressure of about two pounds per square inch tofacilitate removal of the sheets 108 & 110 from the table 194 andtransfer of the sheets 108 & 110 to the molds 186 & 188. Preferably,application of a vacuum to the molds 186 & 188 and cutting off thevacuum to the table 194 is done substantially simultaneously to effectquick transfer of the sheets 108 & 110 to the molds 186 & 188.

With the application of a vacuum to the upper mold 188, and while thetop sheet 108 preferably is still warm from preheating, the top sheet108 is drawn against the three dimensionally contoured mold surface 230of the upper mold 188 causing the sheet 108 to substantially conform tothe mold surface 230, thereby forming the top sheet 108. With theapplication of a vacuum to the lower mold 186, and while the bottomsheet 110 is preferably still warm from preheating, the bottom sheet 110is drawn against the three dimensionally contoured mold surface 230 ofthe lower mold 186 causing the sheet 110 to substantially conform to themold surface 230, thereby forming the bottom sheet 110. To form eachsheet, a vacuum of at least ten inches of mercury and preferably abouteighteen inches of mercury is applied to each mold to draw the sheetsagainst the mold surface 230.

After the sheets 108 & 110 have been transferred to the molds 186 & 188,the upper mold 188 is moved away from the preheating table 194 to enablethe table 194 to be withdrawn from between the molds 186 & 188. Afterthe upper mold 188 has been suitably retracted away from the preheatingtable 194, the table 194 is withdrawn from between the molds 186 & 188and preferably returned to the position shown in FIG. 12 to beginpreheating another pair of sheets 108 & 110 to be formed and molded intoa bladder 40 of this invention.

D. Molding

After the preheating table 194 has been retracted, the molds are broughtto bear against each other, such as is shown in FIG. 14, to join thesheets 108 & 110 together while the sheets 108 & 110 are preferablystill hot to form a seal 66 defining the inflatable chambers and gaspassages of the bladder 40 and defining the gas passages of the integralcontrol flap 52. Preferably, a vacuum is applied to each mold 186 & 188during molding to further facilitate forming of each sheet 108 & 110during molding.

To bring the molds 186 & 188 to bear against each other, the piston 191of the ram 190 is extended further outwardly until the mold surface 230of the upper mold 188 is brought to bear against the mold surface 230 ofthe lower mold 186, sandwiching the sheets 108 & 110 between the molds186 & 188. As a result of the molds 186 & 188 being accurately locatedrelative to each other, the upraised wall portion 232 of each mold 186 &188 preferably sandwiches the sheets 108 & 110 in the region where it isdesired to form the seal 66 of the bladder 40. During molding,sufficient pressure is applied by the molds 186 & 188 to press thesheets 108 & 110 together in the seal region to join them together,airtightly forming the seal 66 and preferably also completing molding ofthe bladder 40.

If desired, the top sheet 108 can be joined to the bottom sheet 110 byultrasonic welding, heat sealing, by use of an adhesive, or anothersealing process to form the seal 66. Additionally, a combination ofpressure from the molds 186 & 188 and one or more of the aforementionedjoining methods, materials, or techniques can also be used in gastightly forming the seal 66. Preferably, the seal 66 is sufficiently gastight to permit each bladder chamber 68, 70 & 72 to be inflated to apressure of at least two pounds per square inch and preferably can beinflated to a pressure of at least about six pounds per square inch toprovide cushioning support to a seat occupant.

After the bladder 40 is allowed to cool for a sufficient period of time,the molds 186 & 188 are separated and the bladder 40 is removed.Preferably, the press 180 dwells at least ten seconds before separatingthe molds to allow removal of the bladder 40. Preferably, the dwell timeis about twenty-five seconds before the molds separate.

Thereafter, if necessary, a trimming operation can be performed to trimexcess sheet material from the periphery of the bladder chambers 68, 70& 72 and control flap 52. Preferably, however, the molds 186 & 188 areconstructed and arranged such that they automatically trim excess sheetmaterial from the bladder 40 when the molds 186 & 188 are brought tobear against each other during molding. If desired, sheets 108 & 110that are die cut to the desired size before preheating can be used toconstruct a bladder 40 that requires virtually no trimming after formingand molding have been completed.

III. SEAT ASSEMBLIES A. Motorcycle Seat

1. Single Bladder Construction

In the assembly of a motorcycle seat 44, such as the seat depicted inFIGS. 15 through 17, the valves 56 are assembled to the control flap 52of the bladder 40 preferably before the bladder is assembled to a seat42. Before assembling the seat covering 102, the bladder 40 ispreferably received in retainer pockets 96 (FIG. 4) in the seat occupantsupporting surface 98 of the foam support cushion 100, such as amotorcycle seat saddle 101, that underlies the seat covering 102 whenassembly is completed. When assembling the bladder 40 to the seat 42,the control flap 52 is also received in a retainer pocket 97 in thesidewall 50 of the foam support cushion 100.

Preferably, the retainer pockets 96 are pre-molded in the foam supportcushion 100 before assembly. Alternatively, if the bladder 40 issuitably inflated, the retainer pockets 96 can be foam-in-place moldedabout the bladder 40 when making the foam support cushion 100 and beforefitting the seat covering 102 over the cushion 100.

As is shown in FIG. 15, the retainer pockets 96 are located where thedriver of the motorcycle, M (FIG. 1), would sit while driving themotorcycle, M. To enable the driver to be able to perform seat comfortadjustments to the bladder 40 while driving the motorcycle, M, thebladder 40 and control flap retainer pocket 97 are constructed andarranged to locate the control flap 52 within easy reach of the driveron the side of the seat 44 that preferably is opposite the throttle. Forexample, if the throttle is located on the right hand side handlebar ofthe motorcycle, M, fie control flap 52 and its associated retainerpocket 97 are preferably located on the left hand side, as is depictedin FIG. 15, to enable the driver to make seat comfort adjustments to thebladder 40 during motorcycle operation without requiring the driver toremove their hand from the throttle.

Preferably, after the bladder 40 has been assembled to the supportcushion 100, the gas supply 60 is connected to the control flap 52. Asis shown in FIG. 16A, to assemble the gas supply 60, the compressor 61is preferably received inside the reservoir bag 63 and the supply line58 is connected to the outlet 65 of the bag 63 and the inlet port 122 ofthe control flap 52 (FIG. 2). The compressor 61 could be exterior of thereservoir bag 63, if desired. The portion of the supply line 58extending from the reservoir bag 63 is connected to the pressure switchT-fitting 67 and the portion of the supply line 58 leading to thecontrol flap 52 with the pressure switch 62 being connected to theT-fitting 67.

Preferably, the gas supply 60 is received and retained in an out of theway location that protects the reservoir bag 63. Preferably, the gassupply 60 is located in a retainer pocket 260 underneath the seat. As isshown in FIG. 17, the retainer pocket 260 can be a pocket molded intothe underside of the foam cushion 100. As is shown in FIG. 15, with thegas supply 60 received in the retainer pocket 260 in the underside ofthe seat cushion 100, the gas supply hose 58 is preferably routedthrough a bore 261 (FIG. 15) in the cushion adjacent the control flapretainer pocket 97 for easy connection to the bladder control flap 52.

Although the bladder 40 is shown having pinch valves 132 in its controlflap and valve assembly 120, the bladder 40 can utilize a modifiedcontrol flap construction 52' (FIG. 8) along with pneumatic valves 164,if desired. The seat 44 can also be constructed with a layer of foamoverlying the bladder 40 and between the bladder 40 and seat covering102, if desired.

2. Dual Bladder Construction

FIGS. 18 & 19 illustrate a motorcycle seat 44' having a driver bladder40, for providing adjustable comfort to a driver of a motorcycle, apassenger seat bladder 40', for providing adjustable comfort to a seatoccupant that is a passenger, P, of the motorcycle, and a pair ofcontrol valve assemblies 160 & 160' for enabling controlled andselective inflation and deflation of each bladder chamber of eachbladder 40 & 40'. As is shown in FIG. 18, the seat 44' has a covering102 over both the driver seat occupant supporting surface 98 and thepassenger seat occupant supporting surface 98'. To enable each chamberof each bladder 40 & 40' to be controllably and selectively inflated,the seat 44' has a driver pneumatic valve assembly 160 and passengerpneumatic valve assembly 160' received in the sidewall 50 of the seat44'.

As is shown in FIG. 19, the driver seat bladder 40 preferably is of thesame construction as the bladder 40 shown in FIG. 15. The passenger seatbladder 40' preferably has thigh chambers 68 and buttocks chambers 70and lacks lumbar chambers 72, if the passenger seat occupant supportingsurface 98' lacks a lumbar support region. Alternatively, if themotorcycle seat 44' is constructed with a lumbar support region, thepassenger seat bladder 40' can be of a construction that is preferablyvirtually identical to the driver seat bladder 40 and which has a pairof lumbar chambers 72.

Although the gas supply 60' is shown in FIG. 19 without a pressureswitch 62, the gas supply 60' for supplying both bladders 40 & 40'preferably can also be constructed having a pressure switch 62. Toenable the gas supply 60' to supply gas to both bladders 40 & 40', thegas supply 60' is preferably connected by a T-fitting 262 to supplylines 58 in communication with each bladder 40 & 40'.

In assembly, the bladders 40 & 40' are received in retainer pockets 96 &96' in the support cushion 100 which is preferably secured to a seatbase 264 that is attached to a chassis of a motorcycle. Preferably, thecontrol flap retainer pockets 97 & 97' in the support cushion 100 arerecessed to accommodate pneumatic valve assemblies 160, if pinch vanesare not used. To enable the pneumatic valve assemblies to be insertedthrough the seat covering 102 into the control flap retainer pockets 97& 97', the seat covering has a pair of apertures 266 & 268 in itssidewall.

To cushion the bladders 40 & 40', the seat 44' preferably has a firstfoam pad 270 between the driver seat bladder 40 and the seat covering102 and a second foam pad 272 between the passenger seat bladder 40' andseat covering 102. If desired, these pads 270 & 272 can be constructedas a one-piece, unitary assembly. If the seat covering is sufficientlypadded, the seat 44' can be constructed without a separate layer of foampadding 270 & 272 between the bladders 40 & 40' and seat covering 102.

After the pads 270 & 272 are placed over the bladders 40 & 40', the seatcovering 102 is fitted over the bladders 40 & 40', foam support cushion100, and seat base 264 to complete assembly of the motorcycle seat 44'.

B. Vehicle Seat

FIGS. 20 & 21 illustrate two preferred embodiments of a bladder 340 &340' of this invention for use in a vehicle seat 300, such as anautomobile vehicle seat or an off-road vehicle seat. The seat has achassis 302 that carries (a) a seat cushion 304 that functions as a seatoccupant supporting surface to support the legs and buttocks of a seatoccupant, and (b) a backrest cushion 306 that functions as a seatoccupant supporting surface to support the back of a seat occupant.

As is depicted in FIGS. 20 & 21, the backrest 306 of the seat 300 hasslightly outwardly extending and spaced apart side support panels 308which preferably help locate an occupant in the seat 300 to properlyposition the seat occupant while also supporting the seat occupant alongboth sides of their back. The seat cushion 304 preferably has a pair ofspaced apart and upraised bolsters 310, also for supporting andpositioning a seat occupant. To support the thigh region of a seatoccupant, the cushion 304 preferably also has a slightly upraised thighsupport cushion region 312.

As is shown in FIG. 21, to provide selectively adjustable comfort to aseat occupant, the bladder cushioning system has a backrest bladder 340'with multiple chambers and which is of one piece, unitary construction.To provide support to the legs and buttocks of a seat occupant, thebladder system also has a seat cushion bladder 340 of multiple chamberconstruction and which is of one piece, unitary construction. To enablethe chambers of each bladder 340 & 340' to be inflated, the bladdersystem has a gas supply 60. To insure that the reservoir bag 63 of thegas supply 60 always has a sufficient supply of gas to initiateinflation of one or more chambers of the bladders 340 & 340', the supply60 preferably has a pressure switch 62 in communication with the gascompressor 61, which, in turn, is preferably received within thereservoir bag 63. To selectively inflate and deflate chambers of thebladders 340 & 340', the bladder system has a valve assembly 314 incommunication with the backrest bladder 340' and another valve assembly316 in communication with the seat cushion bladder 340.

To provide cushioning and support to the legs, thighs, and buttocks of aseat occupant, the seat cushion bladder 340 preferably has at least oneselectively inflatable chamber underlying the buttocks and legs. As isshown in FIG. 21, the bladder 340 has at least one inflatable chamber318 generally underlying the buttocks region. To provide adjustablesupport to the thighs and legs of the seat occupant, the bladder 340preferably has a laterally extending inflatable chamber 320. To enablethe bolsters 310 of the seat 300 to be adjusted, the bladder 340preferably has a pair of spaced apart inflatable seat bolster chambers322. To communicate gas between the seat bolster chambers 322, thechambers 322 preferably can be joined by a gas passage. To facilitateconnection of the gas supply 60 and valves 314 & 316, the bladder 340has a control flap 324 that preferably also is in communication with thebackrest bladder 340'.

To provide cushioning and support to the backside of a seat occupant,the backrest bladder 340' has an inflatable chamber 326 for providingcushioning and support to the lower back or lumbar region of the seatoccupant. To provide selectively adjustable cushioning and support tothe upper back, the bladder 340' can be constructed with an inflatablechamber spaced 328 upwardly from the lumbar chamber 326. To providecushioning and support while helping to position the seat occupant, thebladder 340' preferably also has a pair of spaced apart verticallyextending side support chambers 330 which underlie the side supportpanels 308 of the seat 300.

To receive and exhaust gas from the bladder, the backrest bladder 340'preferably has a control flap 332 that is connected to the control flap324 of the seat cushion bladder 340 by piping 334. If desired, thebladders 340 & 340' can be constructed with a single control flapconnecting the two bladders together. If desired, other gas piping andcontrol flap arrangements can also be used to distribute gas between thebladders 340 & 340' and to enable them to be selectively inflated anddeflated.

IV. USE AND OPERATION

In use, a bladder 40 and air supply system 60 of this invention can beused to provide adjustable support to a seat occupant of a vehicle seat42, such as a motorcycle seat 44, or another type of vehicle seat 300such as an automobile seat or off road vehicle seat. Additionally, thebladder 40 and air supply system 60 of this invention can also be usedto provide adjustable support to a seat occupant of a seat other than avehicle seat, such as an office chair, a recliner, or the like. Inoperation, for the seat 42 shown in FIG. 1, after a vehicle equippedwith a seat 42 having a bladder 40 of this invention has begunoperation, such as after starting the vehicle, the pressure within thereservoir bag 63 is sensed by the pressure switch 62. If the pressure inthe reservoir 63 is below the lower threshold pressure, P₁, the pressureswitch 62 energizes the compressor 61 causing gas to be drawn into thereservoir 63 pressurizing the reservoir 63. The compressor 61 preferablyremains energized until enough gas has been pumped into the reservoir 63such that the pressure within the reservoir 63 rises equal to or abovethe upper threshold pressure, P₂. When the pressure within the reservoir63 rises to a pressure that is at least equal to the upper thresholdpressure, P₂, the pressure switch 62 preferably deenergizes thecompressor 61 leaving the reservoir 63 fully charged and able toinitiate inflation of one or more chambers of the bladder 40.

To inflate a chamber of the bladder 40, an associated valve is manuallyengaged by a seat occupant and urged from its gas retaining positiontoward its gas admitting position causing gas to be admitted from thereservoir 63 into the chamber. For example, if a seat occupant desiresto inflate each lumbar chamber 72 of the bladder 40 shown in FIG. 1, theoccupant engages the lumbar chamber valve 157 and urges it to its gasadmitting position. When the chamber 72 has been inflated until itpossesses the amount of firmness desired by the seat occupant, the seatoccupant releases the valve 157 preferably causing the valve 157 toreturn to its gas retaining position.

During inflation, as is depicted more clearly in FIG. 2, gas flows fromthe reservoir 63, through the supply line 58, through the manifoldpassage 124 in the control flap 52, through a gas passage 84 in thebladder 40, and into the desired chambers 72. As gas flows from thereservoir 63, the gas pressure within the reservoir 63 drops. Should thegas pressure within the reservoir 63 drop below the lower thresholdpressure, P₁, the pressure switch 62 energizes the compressor 61 causingthe compressor 61 to recharge the reservoir 63, as well as, supply gasto the chambers 157 being inflated. When the pressure within thereservoir 63 at least reaches the upper threshold pressure, P₂, thepressure switch 62 deenergizes the compressor 61. Preferably, thecompressor 61 is cycled in this manner, as gas is demanded, to maintainthe desired pressure within the reservoir 63, to supply gas to thereservoir 63 for inflating the bladder 40.

To deflate a set of chambers 72 or simply remove air from the chambers72 to adjust its firmness, the seat occupant engages the valve 157associated with the chambers 72 and urges it to its gas exhaustingposition. When in the gas exhausting position, gas flows from theassociated chambers 72, through its gas passage 84 in the bladder 40,through the outlet passage 128 in the control flap 52, out the exhaustport 130 (FIG. 5), and preferably into the atmosphere.

If, however, the gas supply 60 is a closed system, rather than the opensystem depicted in FIGS. 1 through 4, gas flows out the exhaust port 130into a gas collector where it can be reused. Such closed systemoperation is advantageous where a gas other than air is being used toinflate the bladder 40 so that the gas can be recaptured and reused.

It is also to be understood that, although the foregoing description anddrawings describe and illustrate in detail working embodiments of thepresent invention, to those skilled in the art to which the presentinvention relates, the present disclosure will suggest manymodifications and constructions as well as widely differing embodimentsand applications without thereby departing from the spirit and scope ofthe invention. The present invention, therefore, is intended to belimited only by the scope of the appended claims and the applicableprior art.

What is claimed is:
 1. A seat for supporting a seat occupant comprising(a) a seat base having (1) a seat occupant supporting surface and (2) asidewall joined to said seat occupant supporting surface by a corner,and (b) a bladder having (1) an inflatable chamber carried by said seatoccupant supporting surface and (2) an integral control flap having atleast a portion of said control flap disposed along said sidewall,wherein said control flap is constructed and arranged to facilitate gasflow into or out of said chamber.
 2. The seat of claim 1 wherein saidbladder and control flap together form a bladder assembly that is of onepiece, unitary construction having a portion of said control flap bentaround said seat base corner, and further comprising (a) a gas passagecarried by said control flap that is in gas flow communication with saidinflatable chamber for enabling (1) gas to flow through said passage tosaid chamber or (2) gas to flow from said chamber through said passage,and (b) a valve carried by said control flap which is in operablecommunication with said gas passage for controlling gas flow throughsaid gas passage.
 3. The seat of claim 2 wherein (a) said gas passage isintegral with (1) said bladder and (2) said control flap, and (b) saidgas passage is bent about said seat base corner.
 4. The seat of claim 3wherein said gas passage has a flattened portion overlying said cornerwhere said passage is bent for preventing collapse of said gas passagebend to enable gas to flow through said gas passage bend.
 5. The seat ofclaim 2 wherein said control flap is narrower than the rest of saidbladder and said control flap extending outwardly from said bladder. 6.The seat of claim 5 further comprising a seat covering overlying saidseat base and said inflatable chamber and wherein said seat basesidewall has a pocket for receiving said control flap and said controlflap is disposed in said pocket.
 7. The seat of claim 2 wherein saidbladder chamber and control flap are both constructed of a resilientmaterial and share (1) a common upper wall and (2) a common lower walland further comprising a seal joining said walls together and defining(1) said inflatable chamber and (2) said gas passage in gas flowcommunication with said chamber.
 8. The seat of claim 7 wherein saidbladder, including said control flap, is constructed from a pair ofsheets of a flexible elastomeric material with one of the sheetsoverlying the other of the sheets and said sheets joined together bysaid seal with said seal defining said inflatable chamber and said gaspassage.
 9. The seat of claim 8 wherein said seal defines (1) a firstinflatable chamber and gas passage in gas flow communication with saidfirst chamber, (2) a second inflatable chamber and gas passage in gasflow communication with said second chamber, and (3) wherein both saidgas passages extend into said control flap.
 10. The seat of claim 8wherein said sheets are composed of a urethane.
 11. The seat of claim 2comprising:(a) a gas supply for supplying gas to said inflatablechamber; (b) said control flap further comprises (1) a gas supplypassage branch (i) in gas flow communication with said gas supply andsaid gas passage for enabling gas to be supplied to said inflatablechamber (ii) with at least a portion of said gas supply passage branchhaving a generally flexible sidewall and (2) a gas outlet passage branch(i) in gas flow communication with an exhaust port and said gas passagefor enabling gas to be exhausted from said inflatable chamber to deflatesaid chamber (ii) with at least a portion of said gas outlet passagebranch having a generally flexible sidewall; (c) said valve furthercomprises a valve stem with a pair of legs extending outwardly from saidvalve stem with one of said valve legs overlying said gas supply passagebranch flexible sidewall, the other of said valve legs overlying saidgas outlet passage branch flexible sidewall and said valve stem inoperable communication with said control flap; and (d) said valvemovable between (1) a gas retaining position for retaining gas in saidinflatable chamber wherein (i) the one valve leg is urged toward a gaspassage closing position such that said one valve leg bears against saidgas supply branch flexible sidewall urging said flexible sidewallinwardly pinching said gas supply passage branch substantially closedsubstantially preventing gas flow through said gas supply passage branchinto said inflatable chamber thereby preventing further inflation ofsaid inflatable chamber, and (ii) the other valve leg is urged towardsaid gas passage closing position with said other valve leg bearingagainst said gas outlet passage branch flexible sidewall urging saidsidewall inwardly pinching said gas outlet passage branch substantiallyclosed substantially preventing gas flow from said inflatable chamberthrough said gas outlet passage branch for preventing deflation of saidinflatable chamber; (2) a gas supplying position for inflating saidinflatable chamber wherein (i) the other valve leg is urged toward saidgas passage closing position closing said gas outlet passage branch, and(ii) the one valve leg is disposed in a gas passage opening positionwhere said one valve leg is disposed in a position away from said gaspassage closing position such that said gas supply passage branch is notpinched closed allowing gas from said gas supply to flow into saidinflatable chamber inflating said chamber; and (3) a gas exhaustingposition where the one valve leg is disposed in said gas passage closingposition preventing gas flow through said gas supply passage branch andthe other valve leg is disposed in said gas passage opening positionpermitting gas to flow through said gas passage, through said gas outletpassage branch, and out said outlet port deflating said chamber.
 12. Theseat of claim 2 wherein said valve is a pinch valve constructed andarranged to control gas flow through said gas passage by selectivelyconstricting said gas passage.
 13. The seat of claim 12 comprising:(a) agas supply for supplying gas to said inflatable chamber; (b) saidcontrol flap further comprises (1) a gas supply passage branch in gasflow communication with said gas supply and said gas passage forenabling gas to be supplied to said inflatable chamber and (2) a gasoutlet passage branch in gas flow communication with an exhaust port andsaid gas passage for enabling gas to be exhausted from said inflatablechamber to deflate said chamber; (c) said gas valve further comprises avalve body operably connected to said control flap with said valve bodyhaving a first portion constructed and arranged to selectively pinchclosed said gas supply passage branch and a second portion constructedand arranged to selectively pinch closed said gas outlet passage branchwherein said valve is movable between (1) a gas retaining positionwherein said first portion of said valve pinches closed said gas supplypassage branch and said second portion of said valve pinches closed saidgas outlet passage branch, (2) a chamber inflating position wherein saidsecond portion of said valve pinches closed said gas outlet passagebranch and said first portion of said valve does not pinch closed saidgas supply passage branch permitting gas to flow from said supplythrough said gas supply passage branch and into said chamber, and (3) achamber deflating position wherein said first portion of said valvepinches closed said gas supply passage branch and said second portion ofsaid valve does not pinch closed said gas outlet passage branchpermitting gas to flow through said gas outlet passage branch and outsaid outlet.
 14. The seat of claim 2 further comprising a gas supply ingas flow communication with said gas passage for providing gas toinflate said chamber, said gas supply comprising a reservoir for storinga charge of gas and a pump in gas flow communication with said reservoirfor supplying said reservoir with gas at a pressure greater than thepressure of gas in said inflatable chamber so that said reservoirimmediately communicates gas from said reservoir to said inflatablechamber when said valve is opened.
 15. The seat of claim 14 wherein saidreservoir comprises an inflatable bag of flexible and substantially gastight construction.
 16. The seat of claim 15 wherein said reservoir bagis constructed of a flexible and resilient urethane.
 17. The seat ofclaim 15 wherein said pump is an electric air compressor that has an airinlet and an air outlet with said air compressor received inside saidreservoir bag with its air inlet in communication with air disposedoutside said bag and its air outlet in communication with air insidesaid bag.
 18. A seat for supporting a seat occupant comprising:(a) aseat occupant supporting surface; (b) a bladder carried by said seatoccupant supporting surface with said bladder having an inflatablechamber, a control flap, and a gas supply passage extending from saidcontrol flap to said chamber for communicating gas to said chamber; (c)a gas supply in gas flow communication with said control flap forsupplying gas to said supply passage to inflate said chamber, said gassupply having a reservoir storing a charge of gas and said storagereservoir in gas flow communication with said gas supply passage, a gaspump in gas flow communication with said storage reservoir supplyingsaid reservoir with gas, and a pressure sensing switch in gas flowcommunication with said reservoir for sensing the pressure of gas withinsaid reservoir, said pressure sensing switch connected to said pump forcontrolling operation of said pump, and (1) said pressure sensing switchhaving a lower threshold pressure level wherein said switch energizessaid pump to charge said reservoir with gas when the gas pressure insaid reservoir is less than or equal to said lower threshold pressurelevel and (2) said switch having an upper threshold pressure levelwherein said switch deenergizes said pump when the gas pressure withinsaid reservoir is equal to or greater than said upper threshold pressurelevel; and (d) a gas flow control valve between said storage reservoirand said inflatable chamber, said valve controlling gas flow from saidstorage reservoir to said inflatable chamber.
 19. The seat of claim 18wherein said lower threshold pressure level is about thirteen pounds persquare inch and said upper threshold pressure level is about eighteenpounds per square inch.
 20. A seat for a motorcycle comprising:(a) aseat occupant supporting saddle for supporting a rider of the motorcyclewith said saddle having (1) a seat occupant supporting surface on itstop and (2) a sidewall; (b) a bladder having (1) an inflatable chambercarried by said saddle and (2) an integral control flap disposed alongside said sidewall; (c) a valve operably associated with said controlflap for controlling gas flow into or out of said inflatable chamber;and (d) a seat covering overlying said saddle and said inflatablechamber.
 21. The motorcycle seat of claim 20 wherein said saddle has aretainer pocket in said seat occupant supporting surface of said saddlefor receiving said inflatable chamber and a retainer pocket in saidsaddle sidewall for receiving said control flap wherein said bladder isdisposed in said bladder retainer pocket and said control flap isdisposed in said control flap retainer pocket.
 22. A method of operatinga seat for providing adjustable support to a seat occupantcomprising:(a) providing a bladder having an inflatable chamber a gassupply having a reservoir for storing a charge of gas for supplying gasto the chamber to inflate the chamber, a compressor for charging thereservoir with gas, and a pressure switch having an upper and lowerthreshold pressure level for sensing the pressure of gas within thereservoir and controlling operation of the compressor, and a valveoperably associated with the bladder having a first position forretaining gas in the chamber and a second position for admitting gasinto the chamber; (b) sensing the pressure of the gas within thereservoir; (c) energizing the compressor to charge the reservoir withgas if the gas pressure within the reservoir is less than the lowerthreshold pressure level; and (d) deenergizing the compressor when thepressure of the gas in the reservoir is greater than the upper thresholdpressure level.
 23. The method of claim 22 wherein the lower thresholdpressure level is about thirteen pounds per square inch and the upperthreshold pressure level is about eighteen pounds per square inch.
 24. Aseat for supporting a seat occupant comprising:(a) a bladder having aninflatable chamber; (b) a gas storage reservoir bag in gas flowcommunication with said inflatable chamber and which is composed of aresilient and flexible material constructed and arranged to besubstantially gas tight so as to hold gas at a pressure greater than thepressure of gas in said inflatable chamber; and (c) a gas pump in gasflow communication with said reservoir bag for charging said reservoirbag with gas.
 25. The seat of claim 24 wherein said gas pump is anelectric gas compressor constructed and arranged to charge saidreservoir bag with gas until the gas in said reservoir bag is at apressure greater than the pressure of gas within said inflatablechamber.
 26. A seat for supporting a seat occupant comprising:(a) a seatbase having a seat occupant supporting surface; (b) a bladder carried bysaid seat base with said bladder having an inflatable chamber and a gaspassage leading to said chamber; (c) a valve in operable communicationwith said gas passage for (1) allowing gas flow through said passagewhen said valve is in an open position and (2) opposing gas flow throughsaid passage when said valve is in a closed position; (d) a gas storagereservoir in gas flow communication with said gas passage upstream of(1) said valve and (2) said inflatable chamber for storing a charge ofgas under pressure that is supplied to said inflatable chamber when saidvalve is disposed in said open position, wherein said gas storagereservoir comprises a gas tight bag constructed of a flexible andresilient elastomeric material; and (e) a gas compressor in gas flowcommunication with said reservoir bag for supplying said reservoir bagwith gas.
 27. The seat of claim 26 wherein (1) said gas compressor hasan outlet for discharging gas under pressure and an inlet for enablinggas to be drawn into said compressor, and (2) said gas compressor isreceived inside said reservoir bag having its inlet in communicationwith a gas source exterior of said bag for supplying gas to saidcompressor and its outlet located inside said reservoir bag fordischarging pressurized gas into said reservoir bag.
 28. The seat ofclaim 27 wherein said reservoir bag is constructed of a first wall and asecond wall of a flexible material with said first wall overlying saidsecond wall and joined together by a seal defining an inflatablereservoir chamber therein with said gas compressor received in saidreservoir chamber.
 29. A seat for supporting a seat occupantcomprising:(a) a seat base having a seat occupant supporting surface;(b) a bladder carried by said seat base with said bladder having aninflatable chamber and a gas passage leading to said chamber; (c) avalve in operable communication with said gas passage for (1) allowinggas flow through said passage when said valve is in an open position and(2) opposing gas flow through said passage when said valve is in aclosed position; (d) a gas storage reservoir in gas flow communicationwith said gas passage upstream of said valve and said inflatable chamberfor storing a charge of gas under pressure that is supplied to saidinflatable chamber when said valve is disposed in said open position;(e) an electrically powered gas compressor in gas flow communicationwith said gas storage reservoir for charging said reservoir with gas;and (f) a gas pressure sensing switch in communication with said gas insaid storage reservoir and electrically connected to said gas compressorfor controlling operation of said compressor to cause said compressor tomaintain gas at a pressure of at least about thirteen pounds per squareinch inside said storage reservoir when said valve is closed so thatsaid storage reservoir supplies gas under pressure to said inflatablechamber when said valve is opened.
 30. The seat of claim 29 wherein saidgas pressure sensing switch is constructed and arranged to energize saidcompressor when pressure in said gas storage reservoir is at or belowabout thirteen pounds per square inch and deenergizes said compressorwhen pressure in said gas storage reservoir is at or above abouteighteen pounds per square inch so that said storage reservoir suppliesgas under pressure to said inflatable chamber immediately upon openingof said valve whether or not said compressor is energized at the timesaid valve is opened.
 31. The seat of claim 29 wherein said gas pressuresensing switch is constructed and arranged to maintain gas inside saidstorage reservoir at a pressure that is greater than the pressure of gasinside said inflatable chamber for enabling gas to be supplied from saidreservoir to said inflatable chamber immediately upon the opening ofsaid valve.
 32. The seat of claim 31 wherein gas is supplied from saidreservoir to said inflatable chamber immediately upon opening said valvewhether or not said compressor is energized at the time said valve isopened.
 33. A seat for supporting a seat occupant comprising:(a) a seatbase having a seat occupant supporting surface; (b) a bladder carried bysaid base and having (1) a first pair of spaced apart inflatablechambers in gas flow communication with each other by a firstinterconnecting gas passage, and (2) a second pair of inflatablechambers in gas flow communication with each other by a secondinterconnecting gas passage with said second pair of inflatable chambersspaced rearwardly from said first pair of inflatable chambers relativeto a seat occupant sitting in the seat; and (c) wherein (1) one of saidchambers of said first pair underlies one of the thighs of a seatoccupant and the other of said chambers of said first pair underlies theother of the thighs of a seat occupant when a seat occupant is sittingon the seat, and (2) one of said chambers of said second pair underliesone of the buttocks of a seat occupant and the other of said chambers ofsaid second pair underlies the other of the buttocks of a seat occupantwhen a seat occupant is sitting on the seat.
 34. The seat of claim 33wherein said first pair of inflatable chambers provides cushioningsupport to the femur and ischium of a seat occupant and said second pairof inflatable chambers provides cushioning support to the tuberosity ofischium and ramus of ischium of a seat occupant.
 35. The seat of claim33 wherein said bladder is of one-piece unitary construction comprisinga first wall of a flexible and resilient material and a second wall of aflexible and resilient material with one of said walls overlying theother of said walls and joined by a seal that defines each said chamberof said first pair of inflatable chambers and each said chamber of saidsecond pair of inflatable chambers.
 36. The seat of claim 35 whereinsaid seal also defines said interconnecting gas passages.
 37. The seatof claim 36 wherein said first wall is constructed of a first sheet of aflexible and resilient material and said second wall is constructed of asecond sheet of a flexible and resilient material with said seal joiningsaid first sheet to said second sheet and defining said chambers andsaid interconnecting gas passages.
 38. The seat of claim 37 wherein saidseal is a heat seal of gas tight construction.
 39. The seat of claim 36wherein each of said inflatable chamber pairs is independentlyinflatable.
 40. The seat of claim 39 further comprising (1) a controlflap that is connected to and which extends outwardly from said bladderwith said seal further defining (i) a first gas supply passage in gasflow communication with one of said chambers of said first pair withsaid first gas supply passage extending into said control flap and (ii)a second gas supply passage in gas flow communication with one of saidchambers of said second pair with said second gas supply passageextending into said control flap, (2) a first gas flow control valvecarried by said control flap and in operable communication with saidfirst gas supply passage for controlling gas flow to said first pair ofinflatable chambers, and (3) a second gas flow control valve carried bysaid control flap and in operable communication with said second gassupply passage for controlling gas flow to said second pair ofinflatable chambers.
 41. The seat of claim 33 wherein said bladderfurther comprises a third pair of spaced apart inflatable chambers ingas flow communication with each other by a third interconnecting gaspassage wherein one of said chambers of said third pair generallyunderlies one side of the lower back of a seat occupant and the other ofsaid chambers of said third pair generally underlies the other side ofthe lower back of a seat occupant to provide lumbar support to a seatoccupant sitting in the seat.
 42. The seat of claim 41 wherein saidthird pair of inflatable chambers provides cushioning support to theposterior crest of ilium and erector spinae of the seat occupant. 43.The seat of claim 33 wherein one of said chambers of said bladder has arelief indention for helping to prevent said chamber from bulging,collapsing and undesirably deforming during inflation and while underload.
 44. The seat of claim 33 wherein one of said chambers of saidbladder has a relief indention that divides said chamber into at leasttwo chamber portions.
 45. The seat of claim 33 wherein said inflatablechambers of said second pair are adjacent each other with said chambersseparated from each other by said seal.
 46. A seat for supporting a seatoccupant comprising:(a) a bladder carried by the seat with said bladderhaving (1) an inflatable chamber and (2) a control flap with saidcontrol flap (i) in operable communication with said bladder and (ii) ingas flow communication with said inflatable chamber, wherein saidcontrol flap is comprised of (1) a first wall and a second wallconstructed of a resilient material oriented such that one of said wallsoverlies the other of said walls with a seal joining said walls anddefining a gas passage leading from said control flap to said inflatablechamber, and (2) a split line where said first wall and second wallseparate from each other exposing said gas passage; and (b) a gas flowcontrol valve having a fitting that is received between said first walland second wall of said control flap in gas flow communication with saidgas passage to enable said valve to control gas flow through said gaspassage.
 47. The seat of claim 46 wherein said valve fitting is anipple.
 48. The seat of claim 46 wherein said first wall is constructedof a first sheet of a resilient and flexible material and said secondwall is constructed of a second sheet of a resilient and flexiblematerial.
 49. The seat of claim 48 wherein said bladder and said controlflap are of one-piece integral construction with said bladder and saidcontrol flap constructed of said first sheet and said second sheet withsaid sheets joined together by said seal and said seal defining (1) saidinflatable chamber and (2) said gas passage, wherein said gas passage isin gas flow communication with said inflatable chamber and extends intosaid control flap.
 50. The seat of claim 49 wherein the seat has a seatoccupant supporting surface, a sidewall and a corner adjoining said seatoccupant supporting surface wherein said bladder chamber is carried bysaid seat occupant supporting surface and said control flap is disposedalong side said sidewall.
 51. A seat for supporting a seat occupantcomprising:(a) a bladder carried by the seat with said bladder comprisedof (1) a first wall and a second wall constructed of a resilientmaterial oriented such that one of said walls overlies the other of saidwalls with a seal joining said walls and defining an inflatable chamberand a gas passage in gas flow communication with said inflatablechamber, and (2) a split line where said first wall and said second wallseparate from each other exposing said gas passage; and (b) a gas flowcontrol valve having a fitting that is received between said first walland second wall of said bladder in gas flow communication with said gaspassage to enable said valve to control gas flow through said gaspassage.